• TABLE OF CONTENTS
HIDE
 Front Cover
 Table of Contents
 Introduction
 Soil management
 Crop management
 Pesticides
 Summary
 Reference list of Florida...
 Back Cover














Group Title: Bulletin - Florida Agricultural Experiment Station ; 710
Title: Tomato production on the sandy soils of south Florida
CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00027583/00001
 Material Information
Title: Tomato production on the sandy soils of south Florida
Series Title: Bulletin - Florida Agricultural Experiment Station ; 710
Physical Description: Book
Language: English
Creator: Beckenbach, J. R.
Publisher: Agricultural Experiment Stations, Institute of Food and Agricultural Sciences, University of Florida,
Publication Date: 1966
 Record Information
Bibliographic ID: UF00027583
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Table of Contents
    Front Cover
        Page 1
    Table of Contents
        Page 2
    Introduction
        Page 3
    Soil management
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
    Crop management
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
    Pesticides
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
        Page 38
        Page 39
    Summary
        Page 40
    Reference list of Florida publications
        Page 41
    Back Cover
        Back Cover
Full Text
BULLETIN 710
MAY 1966


AGRICULTURAL EXPERIMENT STATIONS
INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES
UNIVERSITY OF FLORIDA, GAINESVILLE
J. R. BECKENBACH, DIRECTOR

TOMATO PRODUCTION
ON THE SANDY SOILS
OF SOUTH FLORIDA









CONTENTS

Page

Introduction ....-- -----------------.---------------------- 3
Soil Management .---.------------ 4
Crop Rotation -.- -------- -- ---------- 5------ ----------- 5
Soil pH and Liming ..----------------- 6
Irrigation and Drainage -------------------- ---- 7
Drainage 7_.--.------- -------- 7
Subirrigation Tiling .------------------------------ 8
Open Ditch Seepage .--------- --------------------- 8
Down-the-Row Irrigation --------------- ----- 9
Overhead Irrigation ..- ------------------------- 11
Fumigation --_----------. ..---- -------- ----------------- 11
Fertilizers and Nutrition ------------------- 15

Crop Management ---------------------------------------- 16
Varieties --------------- ------------------------------- 17
Planting (Seeding and Transplanting) ----------------- -- -- 19
Cultural Practices ------- ----------------------- 22
Unstaked ...------------------------ --------- 22
Staked and Trellised ----------- ------------ 22
Wide-Row Culture .------ ..--------- -.----------------- 25i
Plastic Mulch ..-- ----------------------------- 27
Nutritional Sprays --- -------- ---------------------- 29
Physiological Disorders ----..-------------- 30

Pesticides ---- -------- ------- 31
Weed Control _----------- ----------------------- 32
Insect Control ....--------------------- -.---- 34
Disease Control -------- ------------------------------------ --- 35
Summary .... --------------------..----------- 40
Reference List of Florida Publications .------------ ---- 41

The use of trade names in this publication is solely for the purpose of
providing specific information. It is not a guarantee or warranty of the
products named and does not signify that they are approved to the ex-
clusion of others of suitable composition.







TOMATO PRODUCTION ON THE SANDY
SOILS OF SOUTH FLORIDA

D. G. A. Kelbert, P. H. Everett, A. J. Overman,
C. M. Geraldson, E. G. Kelsheimer, J. P. Jones,
D. S. Burgis and E. L. Spencer 1 2

INTRODUCTION

The successful production of tomatoes in Florida is a skill
that cannot be acquired simply by reading bulletins. However,
a comprehensive outline of carefully tested and time-proven
practices may be helpful to both novice and experienced growers.
In preparing these suggestions, the authors have availed them-
selves of a variety of source materials, including certain care-
fully conducted research experiments in Florida, plus proven
commercial practices. An attempt has been made to include
information which has to do with the growing of the tomato
crop, regardless of the source of such information. Notation
has been made in some cases where the culture of tomatoes in
the home garden varies from that in commercial fields.
In the 10-year period from the 1952-53 season through 1962-
63 the annual cash value of the tomato crop in the state has
varied from $30,063,000 to $57,773,000". This represents ap-
proximately one-third the total value of all vegetables and
makes tomatoes the highest dollar value vegetable crop in the
state. Ninety-eight percent of the commercial tomato crop is
grown in peninsular Florida. Of this acreage 63 percent is
grown on sandy soils. Fruits are harvested and shipped from
November through June.
Florida tomato growers face more growing hazards than
those found in any other part of the country, resulting in high
production costs. Only the fact that tomatoes bring a premium
price on the winter and spring markets makes this crop profit-
able for Florida growers.
1Associate Horticulturist Emeritus, Associate Soils Chemist (South
Florida Field Laboratory), Assistant Soils Microbiologist, Associate Soils
Chemist, Entomologist, Assistant Plant Pathologist, Assistant Horticul-
turist and Soils Chemist and Head, respectively, Gulf Coast Experiment
Station, Bradenton, Florida.
2The authors wish to acknowledge N. C. Hayslip, Entomologist, Indian
River Field Laboratory, Ft. Pierce, who reviewed the manuscript and
suggested changes where necessary, thereby making this bulletin applicable
to commercial production on the Florida East Coast.
3Florida Agricultural Statistics Vegetable Summary 1963 Issue; Flor-
ida Department of Agriculture, Division of Marketing, Jacksonville.






Florida Agricultural Experiment Stations


Most of the tomatoes are still harvested in the mature-green
stage, although there is now considerable interest in vine-
ripened fruit for shipment to northern markets. This practice
is discussed under the heading "Cultural Practices". Canning
usually accounts for less than 12 percent of the marketed crop.
Canneries operate largely on a salvage basis, utilizing fruits
missed during normal picking operations or fruits from aban-
doned fields.
The frequent rains, heavy dews, and winds encountered
during the growing seasons are generally favorable for develop-
ment and spread of fungus and bacterial diseases. Successful
growers recognize the value of disease control measures and
follow a regular schedule of applying pesticides with the best
equipment available.
Similarly, since the mild winters of south Florida are favor-
able for insect activity the year around, most successful growers
can recognize many of these pests and know how to control
them.
The soils of the principal tomato-producing sections of south
Florida are of two extreme groups: the acid, sandy soils and
the calcareous soils. Proper management of either soil group
requires a thorough knowledge of fertilizer requirements, in-
cluding the need for such nutritional minor elements as man-
ganese, iron, zinc, copper, boron, and molybdenum. Methods
of handling the sandy soils are discussed in this bulletin.

SOIL MANAGEMENT

The success of any tomato variety requires modification of
the environment in which it is grown. Proper cultural opera-
tions affect plant growth through their influence on the environ-
ment surrounding the roots. Specific soil management practices
are necessary to maintain productivity of sandy soils. Moisture
and aeration are assured of being controlled by drainage, irri-
gation, and tillage. The development of fungi, bacteria, and
nematodes which attack tomato can be retarded in soil by ex-
posing them to unfavorable environmental conditions. Nutrition
is controlled with fertilizers and other amendments. An im-
portant part of soil management is the cropping system-the
rotation of different crops, or repetition of one kind of crop.
The prime advantages of planned rotations are control of weeds
and reduction of wind and water erosion.







Tomato Production


Crop Rotation
In some areas of Florida, crop rotation has only limited
application because the narrow range of desirable cash crops
and the high value of land normally encourage intensive mono-
culture of tomato. Repeated tomato crops lead to accumulation
in the soil of micro-organisms which injure the roots of the crop
plant. The density and balance of these plant parasites fluctuate
markedly with the crops grown. Tomatoes grown on newly cul-
tivated land normally escape damage. However, soil-borne dis-
eases, nematodes, insects, and weeds increase in importance the
longer the land is in cultivation, especially if the same crops are
grown repeatedly in the same place. Growers who migrate to
"newly cleared" areas each season may avoid these problems,
but those who return to cultivated fields must establish manage-
ment practices to minimize the seasonal increases of the soil
pests.
Crop rotation is one means of combating those disease or-
ganisms and nematodes which have distinct host preferences.
However, tomatoes in the sandy areas of Florida are affected
by a complex of several diseases and nematodes which sometimes
occur together in the same fields. No rotation has been devised
that is wholly satisfactory.
Several species of crotalaria have been recommended for
nematode control. However, uniformly heavy stands are diffi-
cult to establish. C. spectabilis, which is best adapted to south
Florida summers, is toxic to cattle and therefore little used.
Sesbania is grown in well-drained soils and thrives in low lying
areas which generally flood during summer rains. While making
lush growth itself, it increases nematodes such as sting, stubby-
root, and root-knot. Hairy indigo and hegari make heavy
cover and discourage weed growth. Where economically feasible,
land heavily infested with nematodes, fungi or bacteria can be
converted to pastures of pangolagrass for two or more years.
Pangolagrass supports sting, stubby-root, and spiral nematodes,
but is not a favorable host to root-knot nematodes. Certain soil-
borne diseases may be reduced, but not eliminated, by pasture
rotation.
Various cultural operations are effective in reducing the
amount of disease-inciting agents and nematodes accumulated
in the soil during the crop season. After harvest all crops
should be destroyed to prevent further development of nema-







Florida Agricultural Experiment Stations


todes and diseases affecting the plant roots. Other proven
methods of reducing the incidence of soil-borne diseases and
nematodes follow, but unfortunately, both methods result in
soil which is very susceptible to water and wind erosion.
1. Clean fallowing-plow the land regularly during the hot
months of the year to expose the soil to the dry heat of
the sun and to prevent weed growth.
2. Alternate flooding and drying-during the hot months of
the year flood the land as deeply as practical for 2 weeks.
Drain, and cultivate for 2 weeks. Flood again for 2
weeks. This practice is limited to low lying areas where
flooding can be accomplished.

Soil pH and Liming
As the pH decreases below 6.0, a condition which might be
termed an "acidity complex" becomes increasingly important
as a deterrent to good growth and quality. This complex in-
cludes such factors as increased leaching, aluminum and man-
ganese toxicity, decreased molybdenum availability, decreased
nitrification, and other activities of soil micro-organisms. Lim-
ing increases the cation exchange capacity and promotes a
much more favorable pH, and the required calcium in the soil
for tomato growth. Although the availability of such nutrients
as manganese, iron, zinc, and boron decreases as the pH in-
creases above 6.0, optimum production of tomatoes is associated
with pH values approaching 7.0. Where pH values of 6.5 to 7.0
are maintained, additions of minor elements to the soil and/or
by foliar sprays are a necessity.
Approximately 3 to 4 tons per acre of high calcium lime-
stone or dolomite are necessary to raise the pH of acid flatwood
soils from 4.5 to about 6.5. On virgin land, lime should be ap-
plied at least 3 to 6 months before planting and mixed to a
depth of 6 to 12 inches. Hydrated lime can be used for a quicker
reaction; 0.74 pounds are equivalent to 1 pound of calcium car-
bonate (high calcium lime). Basic slag which contains phos-
porus, manganese, iron, and small amounts of other plant
nutrients has an equivalent value of about half that of calcium
carbonate.
When soil is used several seasons at least 1/2 ton of lime is
recommended for each crop season if the pH is 6.5 to 7.0 and
more if the pH is lower.







Tomato Production


Irrigation and Drainage
Important factors in growing tomatoes are an ample water
supply for irrigation, and facilities for rapid and thorough
drainage after heavy rains.
The sandy soils of the east and west coasts of south Florida
have underlying artesian water at depths of less than 100 feet
in some sections to more than 1,000 feet in others. This water
varies in salt concentration, showing a tendency toward increas-
ing salt content in wells that are being extensively pumped.
Before leasing or buying land it is advisable to test existing
wells for salt content, or, if it is planned to drill wells, it is
advisable to check neighboring wells to determine suitable depth
and salt concentration. Wells with total soluble salts in excess
of 1,400 ppm should be avoided.
In some locations it is possible to drill excellent shallow wells
to about 100 feet for volume pumping. Water from such wells
usually is less hard than that from artesian wells, and usually
has a lower salt content.
Ponds or small lakes can seldom be relied upon as a source
of water supply during periods of drought. Since ditch water
may contain nematodes, soil fungi, bacteria, and weed seeds, it
is advisable for the grower who is using new land or chemically-
treated old land to use well water as an irrigation source.

Drainage
Tomatoes do best on fairly rich, well-drained soils. Unfor-
tunately, these two qualifications seldom occur together in sandy
soils of peninsular Florida. Most naturally well-drained sandy
soils (Lakewood, St. Lucie, Norfolk, and Blanton types) are
very low in organic matter and, conversely, most sandy soils
with somewhat more organic matter (Leon, Parkwood, and
Portsmouth types) are poorly drained. Commercial growers
find that it is much simpler to drain and farm the flat, richer
soils than to attempt to farm the naturally well-drained soils.
These latter types are more suitable for tree crops than for
vegetables.
Drainage on flat soils is provided by ditching if there is
sufficient natural slope to the land to carry water into lateral
and main ditches; otherwise diking and pumping off the excess
water is necessary. An adequate main canal is essential in the
drainage of large areas. When numerous tracts of land are







Florida Agricultural Experiment Stations


involved, these canals are usually financed through drainage
districts on a tax basis. Growers operating on large tracts of
flat land generally ring their fields with secondary canals. Soil
from the canal or "rim ditch" is used to form a dike. Pumps
are placed in strategic locations, and excess water is pumped
from the rim ditch around the field over the dike into a drainage
canal, or into adjoining undeveloped land. In some sections the
pumps are installed so that during dry weather they can be re-
versed and used for irrigation.
In the management of individual fields, a grower has a
choice of methods of handling drainage and irrigation. Often
combinations of these methods can be adopted. The four types
are briefly described as follows.

Subirrigation Tiling
This is the most expensive, but in many cases the most
satisfactory method of water control. It is used on such soils
as those of the Leon series, which are underlaid by an organic
or other hardpan layer at a depth of 18 to 36 inches. The clay
tile lines are laid at a depth of 18 to 22 inches, usually 20 or
more feet apart, depending upon the depth to the hardpan. The
land is carefully leveled, and concrete "pockets" are set at both
upper and lower ends of the tile system, from which drainage
and irrigation can be controlled. This method of water control,
while ideal for land that is to be farmed intensively year after
year, is not being used to a great extent in new land development
because of the expense of installation.
A modified type of subirrigation utilizing clay tile and simi-
lar principles is extensively used in some areas. In this method
tile are laid from ditch to ditch across a field at proper intervals,
ending in ditches on either side of the field. The water table is
controlled by adjustable dams placed in the ditches. The effi-
ciency of this method compares favorably with the other type
of subirrigation outlined above, and the cost of installation is
substantially less.

Open Ditch Seepage
This method (Figure 1) is used for both drainage and irri-
gation and is adaptable to most farming areas. Open shallow
ditches (variable in depth depending upon soil texture) are
broken out each cropping season in somewhat the same pattern







SiE y Ti ._ .&....... .





















Figure 1.-Open ditch for irrigation and drainage. Wooden dams permit better
control of water table in sloping land.
as tile lines are laid for subirrigation. The area between two








these to fit their equipment. Lands of wider widths may be
A. h 1





PtwA







suitable for irrigation, but drainage is not rapid enough to take
care of extremely heavy rains. Both tiling and open-ditch
seepage are best adapted to situations where free flowing wells

are available.

Down-the-Row Irrigation
A gentle slope is necessary where this method is used so
that water from the transport ditch located at the highest part
of the field can flow slowly by gravity on the soil surface between
the rows and seep into the beds in the process. This method
is sometimes used to supplement seepage irrigation when the
latter proves to be too slow. The chief advantage of this method
is low cost, requiring only labor to make ditches and to shift
the water from one row to another as irrigation is completed.
Sometimes it is necessary to build low dams across the middles
if the fall is too great and water flows too rapidly. The object







Florida Agricultural Experiment Stations


is to soak the beds each time irrigation is applied. Care must
be taken to prevent standing water, especially in low pockets,
or roots will be damaged.
A recent modification of this method of irrigation and drain-
age combination is the so-called "wide row" culture, shown in
Figure 2. In this system irrigation-drainage ditches are made
between each planted bed containing one or two rows of plants.
The ditches are actually the row middles and the water furrow
is made slightly deeper than the base of the bed. Water is fed
into these ditches from a main ditch at the upper end of the
rows and flows by gravity to the lower end, where the excess
water is carried off by a drainage ditch. The irrigation ditches
can be used for drainage during wet weather.
The principal disadvantage of this method is that during
prolonged dry periods, continuous irrigation through the ditches
keeps the water moving up through the soil. This limits root
penetration, since roots will not grow into poorly aerated soil.
Also it tends to move soluble salts to the soil surface, where
they are deposited as evaporation occurs. Tomato plants grown
under such conditions are extremely susceptible to certain
physiological disorders, such as blossom-end rot. This can be
especially serious on soils such as the Leon series which are
inherently acid.

Figure 2.-Wide row cultivation with alternate rows and ditches.


~~PA
WIM z -e-I
Li ~ ~ ;s q


A~C-~J1~'l







Tomato Production


Overhead Irrigation
Water may be pumped through portable or other pipes and
applied through "overhead" irrigation systems. Advantages are
that (1) the method moves irrigation water from the soil surface
down, which prevents accumulation of salts on the surface, and
does not establish a shallow water table to limit depth of root
penetration; and (2) the method is useful on land not level
enough for other methods. Disadvantages are (1) the initial
cost of pumps, pipe, and sprinklers and the labor cost required
for irrigation. (2) Pollination of flowers may be interfered
with, and insecticides and fungicides may be washed off the
leaves and fruits. (3) Fungus diseases will increase rapidly
unless care is taken to irrigate early in the day, so that plants
will dry off before nightfall. (4) Fertilizer may be leached out
of the root zone.

Fumigation
Good cultural practices retard the build-up of some soil
pests. But for control of those pathogenic organisms that can
survive in the soil in the absence of a host plant or those which
grow on a wide range of hosts, soil fumigation prior to planting
is recommended. The use of fumigants is particularly important
on nematode-infested land. Some of the more common nema-
todes which damage tomato roots are root-knot (Meloidogyne
spp.), stubby-root (Trichodorus spp.), sting (Belonolaimus
spp.), awl (Dolichodorus spp.), lesion (Pratylenchus spp.), and
dagger (Xiphinema spp.). There is, at present, no recommenda-
tion for nematode control on established tomato plants. There-
fore, fumigation must be done before planting.
The success of soil fumigation depends on proper preparation
of the land for treatment, choice of the most effective chemical
against the particular pathogens, careful attention to the appli-
cation procedure, and proper handling of the treated area during
the crop season to minimize recontamination.
The land to be fumigated should be free of crop debris. Plant
parts incorporated into the soil by cultivation must be decom-
posed prior to treatment, since fungi and nematodes remaining
in such plant tissue are not destroyed by the fumigant. The
soil should be of seedbed tilth and of uniform texture so that
the fumigant vapors will move evenly through it. Soil moisture
should be adequate for seed germination for 2 to 3 weeks prior





Chemical Formulation


Vapam Liquid miscible
with water

Vorlex Liquid miscible
with mineral
spirits
Vorlex-201 Liquid miscible
with mineral
spirits
Nemex Liquid miscible
with mineral
spirits
Mylone Solid
(50 D)
EDB
(W85) Liquid miscible
with mineral
spirits
D-D Liquid miscible
with mineral
spirits

* X denotes that control is achieved.


Table I.-Recommended fumigants for pre-planting soil treatment.


Rate / Single
Chisel/1000 Application
Ft. of Row Method Diseases


5 qts. Inject 5" deep X*
broadcast streams
8" apart.
6 pts. Inject 6" deep X
broadcast streams
8" apart.
6% pts. Inject 6" deep X
broadcast streams
8" apart.
6% pts. Inject 6" deep X
broadcast streams
8" apart.
9 lbs. Incorporated in X
beds.

1% pts. Inject 7" deep
broadcast streams
12" apart.
2% qts. Inject 7" deep
broadcast streams
12" apart.


Controls
Nematodes


X


X


X


X


X


X


X


Weeds


X


X


X


X


X







Tomato Production


to treatment to insure better pest control. All soil amendments
should be made either before or at the time of treating.
Fumigants vary in effectiveness against soil pests. It is
necessary that the grower recognize the relative importance
of diseases, nematodes, and weeds in his field and choose the
fumigant which is best adapted for the purpose (Table 1).
Vapam, Vorlex, Nemex, Vorlex-201, and mylone are combina-
tion fungicides-nematicides- herbicides. Ethylene dibromide
(EDB) and D-D are nematicides. Guidance from the county
agricultural agent may be sought in evaluating the best fumi-
gant for a particular situation.
Fumigation procedures are not designed to eliminate all soil
pests from the field. The goal is to establish optimum growth
conditions for the crop for as long after planting as is economic-
ally profitable. Single stream in-the-row application of the liquid
fumigants, which fumigates a limited volume of soil in the bed,
is designed to protect the plant root system from infection for
about eight weeks. This method of placement is profitable for
the mature-green harvested crop, but longer protection is needed
for the vine-ripened culture. The number of harvests may be
increased by initially expanding the volume of the fumigated
bed. This is accomplished by injecting the chemical at two or
three points in the width of the bed (Figure 3). In each case
the rate of the material applied per stream remains the same.
The solid formulation of mylone may be broadcast in a 2-foot
band on the soil surface and incorporated as the tractor disks
throw up the bed. The ease with which mylone is applied makes
the material especially practical for home gardeners.
Maximum pest control with any chemical at a given rate is
dependent on placement which is governed by the depth of and
distance between streams. Adequate soil moisture is necessary
at time of bedding and treating in order to prevent the fumigant
vapors from escaping prematurely. Good moisture also tends
to lower the soil temperature when treatment is made during
hot weather. To help contain the fumigant vapors and main-
tain soil moisture, beds should be formed and compacted with
a bed press.
There has been some interest in mulching crops with plastic
film for weed control and the conservation of nutrients and
water. Application of the film at time of fumigation enhances
the benefit of the treatment by sealing vapors in the bed (Figure
4) and preventing recontamination.







Florida Agricultural Experiment Stations


... tE .' ... .... -,Alf r




Figure 3.-Chisel applicator used to apply soil fumigants prior to planting.

The waiting period necessary between treatment and plant-
ing varies with the weather, the material used, and the method
of planting. The average waiting period is 2 weeks. This may
increase to 3 or 4 weeks if the temperature is low or if heavy
rains seal the beds. Seeded crops are less sensitive to residuals
of the chemicals than are transplants. The beds may be aerated
a couple of days before transplanting by opening a narrow
furrow in which the plants will be placed. In case plastic has


Po,, of injetion.
6 inches deep






Bed surface mulched with
Bed surface unsealed 1.5 mil plastic film

Figure 4.-Zones of effective control of soil pests by in-the-row fumigation.
Bed formed and compacted by bedpress.







Tomato Production


been used, the plant holes should be cut a few days before seed-
ing or setting. Every precaution should be taken to maintain
the treated area free of contamination. Transplants should be
free of disease and nematodes when placed in the fumigated
bed. Cultivators should be adjusted so that soil from between
the beds is not thrown up around the plants early in the season.
Herbicides and soil fungicides have been developed for weed
and fungus control on infested established crops. However, no
post-planting nematicide is recommended for nematode-infested
tomatoes. Crops infested late in the season can be improved by
special attention to moisture and nutrition. Recognizing that
the root system of the plant is restricted by nematodes, the
grower should place fertilizer where the roots can absorb it.
Water tables should be maintained at constant levels in order
that moisture will not be limiting on the infested plants. By
forcing growth of new roots continuously, the grower may take
advantage of the plant vigor to keep crop growth ahead of nema-
tode damage.

Fertilizers and Nutrition
Fertilizers and other supplements should be added so that
all nutrients will be available to the crop in quantity and balance
for optimum production during the entire growing season. Be-
cause of the many and widely varied types of culture used for
tomatoes it is impossible to make recommendations that will
cover all cultural practices. Nutrients should be supplied on
the basis of expected production.
Analysis of average tomato crops indicates that 5 pounds
of N, 2 pounds of P205, and 8 pounds of K20 are required to
produce 1,000 pounds of tomatoes. Because adequate phosphorus
is most important in the younger stages of growth and because
it does not leach, a 4-8-8 analysis is utilized initially, followed
during the later stages of growth by a top-dresser without
phosphorus. Thus a wide row type of culture (about 1,200 un-
pruned plants per acre) might be expected to produce 500
bushels (25 pounds of fruit per plant) per acre during a 4-week
harvest period, and 1.5 tons of 5-2-8 fertilizer equivalent would
be required. Because of variance in soil organic matter less
nitrogen may be required; and when leaching occurs, more
nitrogen and potash will be required. With a vine-ripe, trellis
type of culture (about 10,000 pruned plants per acre) a 1,500







Florida Agricultural Experiment Stations


bushel (9 pounds fruit per plant) per acre yield during a 3 to
4 month harvest period would require 4.5 tons of 5-2-8. Other
nutrients such as calcium, magnesium, sulphur, and all the minor
elements should be considered in the same manner. A liming
practice or minor element program that is satisfactory for the
500 bushels per acre yield would in most cases not be adequate
for the 1,500 bushels per acre yield. Because liming supplements
are relatively insoluble and because of lack of translocation of
calcium within the plant, a calcium deficiency can be and often
is a deterrent to obtaining optimum yields and quality.
Additions of fertilizer, decay of organic matter, and leaching
due to rainfall are the major causes in variation of nutrient
concentration and balances. A system of soil testing which in-
dicates the concentration and balance of nutrients in the soil
solution during the growing season is proving very helpful but
is still in the development stage.
Organics in fertilizers are not recommended, because their
cost is about triple that of equivalent chemical nitrogen, and
their breakdown and resultant nutrient release cannot be con-
trolled by the grower. A cover crop which provides fibrous
material for better aeration and water movement is recom-
mended. Fertilizers should be applied approximately every week
or two, as this permits better nutrient control and also prevents
excessive losses due to leaching. Relatively small amounts of
fertilizer are utilized by small plants. However, as much as 50
pounds of nitrogen per acre per week can be utilized by a crop
which has a concentrated production (wide-row, unpruned
plants). In order to obtain optimum production, the nutrient
must be present when required.
Plastic mulches are now being tested, under which all the
nutrients required for 1,500 bushels per acre can be supplied
in one application for the entire season. Most recent develop-
ments tend toward increased yields, improved quality, and a
greater return per dollar invested.
All of the above considerations are based on adequate control
of water maintaining as consistently as possible a constant,
relatively high water table.

CROP MANAGEMENT
Crop management includes the choice of varieties, planting
(seeding and transplanting), cultural practices (staking, trellis-







Tomato Production


ing, wide-row culture, plastic mulch), nutritional sprays, and
protection against physiological disorders.

Varieties
Use of commercial varieties of tomatoes over the past years
has followed a pattern similar to that of many other vegetable
crops. Good varieties seldom are popular for more than 10 years.
They are gradually displaced by new varieties which are supe-
rior in one or more features (Figure 5).
Grothen's Red Globe was the standard variety for winter
production on the sandy soils in many areas, but has now been
largely displaced by Wilt-Resistant Grothen's Globe, which
carries resistance to Fusarium wilt. At present these varieties,
because of their earliness, are planted in the fall only in limited
amounts in the East Coast area.
Homestead 24 is the present commercial standard for ma-
ture-green harvest in all of the major producing areas of the
state.
Limited plantings of old varieties such as Rutgers and Mar-
globe may be found, but the acreage of these is insignificant.


Figure 5.-Fruits of six standard varieties. Top (left to right) Manalucie,
Indian River, and Monapal. Bottom (left to right) Homestead 24, W. R. Grothen's
Globe, and Marion.







Florida Agricultural Experiment Stations


There is much interest in the new varieties Marion and Floralou.
The latest introductions Immokalee, Floradel, and Super-
market have shown much promise.
The disease-resistant variety Manapal is planted quite ex-
tensively for mature-green harvest in some areas; the variety
Indian River is planted to some extent. A new determinate type
tomato, Supermarket, which is similar to Homestead 24, has
shown much promise in trials and may replace Homestead 24.
It has resistance to both gray leaf spot and Fusarium wilt.
During the past 10 years there has been a gradual increase
in the acreage devoted to the production of "vine-ripened" to-
matoes. This type of culture requires varieties with specific
horticultural characters. The varieties Manalucie and Indian
River have been the standard for this type of culture since their
release in 1953 and 1958, respectively. The new variety Mana-
pal has proved adaptable for vine-ripened harvest and in some
areas is replacing Manalucie by producing higher yields and
more uniform quality fruits and by having more resistance to
cracking than the older variety. The new variety Floradel is
considered superior to other varieties for vine-ripe culture in
yield potential.
All of the above varieties have faults, typical of which is
the tendency of Manalucie to crack badly under adverse condi-
tions and the very serious susceptibility of Homestead 24 to
gray leaf spot and graywall phase of blotchy ripening.
Most of the areas now being farmed are infested with Fusa-
rium wilt and other soil-borne disease-producing organisms.
These disease organisms are not usually serious on virgin soils
or soils which are farmed to tomatoes for the first time. For
this reason it is important to select a variety that has resistance
to as many diseases as possible, as well as being adaptable to
the soil type in which it is to be grown.
The varieties Manalucie, Manapal, and Indian River are all
immune to or have a high degree of resistance to Fusarium wilt
(Race I), gray leaf spot, leafmold, early blight, and graywall.
Homestead 24 and W. R. Grothen's Globe have full resistance
to Fusarium wilt (Race I) but are very susceptible to gray leaf
spot and other leaf diseases. See Table 2 for more complete
information. The new variety Supermarket is resistant to Fusa-
rium wilt (Race I) and gray leaf spot. Most new varieties being
released by plant breeders working in the southeast carry re-
sistance to Fusarium wilt (Race I) and may be resistant to at







Tomato Production


least some of the leaf spotting diseases. A newly discovered
race of Fusarium, found in some sections of the state, has
largely nullified the benefits of Fusarium wilt resistance in these
areas.
Growers should be skeptical about accepting new varieties.
Interesting new varieties should be tried on a small scale to
allow judgment of their adaptability to a particular area and
to test their market acceptance. Growers should also realize
that one function of the progressive seedsman is to improve
varieties by careful selection in the seed fields. Such selection
results in different strains of a variety which may differ marked-
ly from each other. It is desirable for growers to test on a small
scale strains with which they are not familiar, and to re-order
those strains which prove to be best adapted by actual field test.
Most growers normally do not concentrate on one variety, but
usually grow two or more varieties each season. Table 2 gives
pertinent information about the most important tomato varieties
planted in Florida.

Planting (Seeding and Transplanting)
Most growers using new or relatively new land now seed
tomatoes directly in the field. In many instances, supplemental
seedbeds are grown to insure a supply of plants if the field-
seeded crop fails. When seeding directly in the field, mechanical
seeders are used with seed dropped about every 3 to 4 inches.
These young seedlings are later thinned to 12 to 18 inches apart
within the row for staked or trellised plants and 18 to 48 inches
apart for unstaked plants. Tomatoes seeded directly in the field
will mature earlier than those transplanted. Direct seeding in
the field is not generally recommended on land over-run with
weeds unless a herbicide is used. Field-seeding takes much more
seed than is required where plants are set from beds, but this
cost plus that involved in an additional hoeing operation may
still be less than the cost of setting plants and maintaining seed-
beds. In the thinning process many seedlings from seeded fields
are salvaged for transplanting.
The growing of plants in seedbeds has the advantage of con-
centrating a large number of plants in a small area for the first
three to five weeks. Such plants may be protected by covers
against heavy rains or frosts, and may be easily irrigated in
dry weather.









Table 2.-Description of varieties.

Harvest as Vine Type Disease Resistancet Season Maturitytt
Mature Vine Deter- Semi- Reg- Gray- Win- Mid-
green* ripe minate det. ular wall C A St W Fall ter Spring Early season Late

Homestead 24 x x x x x x x
Indian River x x x x x x x x x x x x
Manalucie x x x x x x x x x x x
Manapal x x x x x x x x x x x x
Grothen's Red Globe x x x x x
W. R. Grothen's Globe x x x x x x
Marion x x x x x x x x
Floralou x x x x x xx x x x x
Supermarket x x x x x x x x
Immokalee x x x x x x x x x x
Floradel x x x x xxx x x x x x


* CAUTION: All varieties should be
in full mature green stage when har-
vested. Some varieties, especially dur-
ing cold periods, will not color proper-
ly if harvested at the immature stage.


-Cladosporium
=Alternaria
=Gray leaf spot
Stemphylium
=Fusarium wilt
(Race 1)


ttEarly=70 days or less
Mid-season=75 days
Late=77 days or more






Tomato Production


Growers usually try to locate seedbeds on newly cleared land.
When this cannot be done, the seedbed area should be uniformly
treated with a soil fumigant. A methyl bromide mixture, such
as MC-2, when used as directed by the manufacturer, is recom-
mended for such fumigation. This material will kill root-knot
nematodes and most weed seeds. It will also destroy certain
insects and soil-borne plant pathogens. Recontamination of
treated areas must be avoided. (See Florida Agricultural Exten-
sion Service, Circular 98B, Vegetable Production Guide: Toma-
toes.)
The seedbed area is generally given about 3,000 pounds per
acre broadcast of 4-9-3 or some other similar type seedbed fer-
tilizer. Beds 4 feet wide are formed by making a furrow at the
desired bed width, with careful attention paid to forming a
smooth, level bed surface. Seeds are usually sown in shallow
rows across the bed, the rows being from 5 to 6 inches apart.
Large-scale growers use seeders and plant lengthwise. Exces-
sive crowding of plants should be avoided to prevent growth
of weak, spindly plants.
It is desirable to use seedbed covers for protection against
rain or frost. Translucent plastic covers are best, since they
protect plants from rainfall damage, and leaching of fertilizer
is avoided. Some growers produce suitable plants without such
covers, substituting mulches of sawdust or pine needles to keep
beds from washing in heavy rains and to prevent sand from
splashing on the plants.
A definite schedule of fungicide and insecticide applications
should be started with plants in the seedbed, and continued
through the whole period of growth of the crop. An "insoluble"
copper drench (12 pounds of one of the insoluble copper fungi-
cides to 100 gallons of water) is recommended for the control
of "damp-off" when it appears. Usually one application at the
rate of 6 gallons per 100 sq. ft. is sufficient. Beds should be
treated for mole-cricket control before seeding. In winter or
spring seedbeds, a weekly spray of fungicide should be applied,
together with 1 pound of 15 percent parathion per 100 gallons
if leafminers are present. Two pounds of 50W DDT may be
added if worms appear. If late blight [Phytophthora infestans,
(Mont.) DBy.] threatens, maneb may be used as a preventive.
Dichlone or zineb may be alternated with maneb for use in a
3-day schedule. In fall seedbeds a copper plus maneb spray, or
in some areas a combination of copper and streptomycin, should






Florida Agricultural Experiment Stations


be used for bacterial spot control. With seedbed rows 5 to 6
inches apart the stems and under surfaces of leaves can be
thoroughly coated with fungicide.
Setting plants in the field is done either by hand or by trans-
planting machinery, depending on the size of the operation and
the nature of the soil. Experiments over a period of years have
not demonstrated any consistent advantage in using starter or
soluble fertilizer solutions, although in some cases the plants
have grown a little faster initially where such solutions were
used on sandy soils. This has not affected ultimate yields but
has made the crop a little earlier.
It is important that tomato plants be watered-in when set.
Losses from "damp-off" may run high under some conditions,
and it has been found that the addition of a fungicide to the
Transplant water will reduce such losses. Dichlone at 1 pound
to 100 gallons or one of the basic copper fungicides (2 pounds
metallic copper per 100 gallons) may give excellent disease con-
trol without damage to the plants. An alternative method of
reducing losses from this trouble is to spray the plants carefully
with either of the above-mentioned fungicides before pulling
from the seedbed, being particularly careful to get thorough
coverage on the stems.

Cultural Practices
A number of cultural practices for tomato growing have de-
veloped through the years. Several of these are now being used
in the tomato-producing areas of south Florida. A brief discus-
sion of the more widely used methods follows.

Unstaked
This method is more commonly called ground or bush culture
and refers to the practice of not providing any artificial means
of support for the tomato vine. The tomato plant normally
sprouts a side shoot or "sucker" at each node or leaf axil. These
suckers are not removed from unstaked tomato plants. As the
side shoots grow, the plant takes on the appearance of a bush
rather than a vine. (See Figure 6.)

Staked and Trellised
The suckers or side shoots are removed with both of these
methods. This practice is known as pruning. In staked toma-







Tomato Production


f,. 4,' .rM "',
-r- -.r^rC. ..- 9 ?























Figure 6.-Bush type growth of unstaked, unpruned tomato plants.
toes after the suckers are pruned, the main stem is tied to a
stake. (See Figure 7.) These stakes are usually of cypress, 4
to 5 feet long and 1/, inch x 1 inch or 1 inch x 1 inch in cross-
section. Many growers who stake their tomatoes prune to a fork
instead of a single stem. The growth habit of the tomato plant
is such that an exceptionally vigorous sucker is produced in the
leaf axil just below the first fruit hand; this sucker is not re-
moved when plants are pruned to a fork. The fact that tying is
slightly more difficult when plants are pruned to a fork is more
than counterbalanced by (1) increased foliage to protect fruit,
(2) increased leaf surface to produce plant metabolites, and (3)
additional yield of fruits produced along the second stem.
A relatively new method of supporting tomato plants, called
"string trellising", has been developed and has replaced in some
Fiue6 -uhtp rot fusaeuprndtmt lns
tosate h ucesae rnd temi se stidt
stk. SeFiue7. hsesaesaeusal o yres
to fet lng nd 1inc x inh o 1 nc x inh i crss
seton an roes h sae hirtmaos rnet afr
inta fasngese.Tegrwhhbto tetmt ln
issc ta nexetonlyvgoossukri pouedi h
lefailjs blwth istfut ad ti uce s o e
moedwhn lat ae ruedt afok.Th fc tattyngi
slgtymr ifcl hnpansaepue oafr smr
thn outrblace y 1)inrasd olae o roet rut
(2 nresdlafsrac opodc latmtboie, n 3
adiinl il f rispodcdaon h ecn tm
A reativly ew mtho of upprtin toato lans, clle
iitin relsig, a be dvloe adha epaedi sm



























Figure 7.-Typical staked tomato field.

areas the old method of tying plants directly to the stakes.
Stakes are placed between the plants in the row, and a contin-
uous string is applied horizontally from stake to stake on both
sides of the plants. The string is dispensed from a ball and a
turn (not tie) is made around each stake at the proper height
to support the plant at various stages of growth. This method
requires less labor and has proved very effective.
The principal difference between staked and trellised culture
is in the method of supporting the plants. There are several

Figure 8.-Erecting trellis in field of young plants.


-mow.
", 4 O


"4- QL;
-. .1







Tomato Production


types of trellises being used, but the most common type is usu-
ally constructed as follows. A heavy wire is strung over the
row between anchor posts spaced at certain intervals along the
row (Figure 8). Between anchor posts the wire is supported
by 2 inch x 2 inch posts at a height of 4 to 5 feet above the top
of the bed. A strong binding twine is tied loosely in a non-slip
knot at the base of each plant. The twine is then spiraled loosely
around the main stem and tied to the overhead wire. This pro-
cess is repeated as the plant grows, continuing the spiral up-
ward. In this way the plant is supported in an upright position.
Great care should be given to the construction of the trellis,
since it is placed under considerable stress by the weight of the
tomato vines and fruits (Figure 9).


.. .. -.




Figure 9.-Harvesting tomatoes from mature, trellised plants.

Wide-Row Culture
This is perhaps the most recent trend in tomato culture to
be adopted on a fairly large scale. At present its use is centered
in the Manatee-Ruskin area, where it originated.
The wide-row method consists of a single row or double rows
of plants set or seeded on high, wide beds as shown in Figure 2.
Single-row plantings have rows separated by combination irriga-







Florida Agricultural Experiment Stations


tion and drainage ditches 9 to 14 feet apart; double-row plant-
ings usually have ditches 21 feet apart with two rows (7 feet
apart) planted high on the bed between the ditches.
In this system a modified method of pruning and staking is
used, and plants are spaced from 24 to 48 inches in the row.
Whereas some growers prefer to prune side shoots to a limited
extent, others continue the pruning to form a fork, and then
allow the plants to produce as many side shoots as possible. The
plant is tied by gathering three or four main stems and fasten-
ing them loosely with a light jute twine to the stake. Two
additional things are usually made, at which time the upper
branches are gathered and tied loosely to the stake. As a result
of the loose tying, the plants usually slip to the ground around
the base of the stake, where they spread to cover the entire area
provided for the plant's growth (Figure 10).
The greatest benefit of the wide-row culture, which reduces
the plant population approximately 80 percent from the con-
ventional staked crops, appears to be gained from its superior
water-control system, particularly from the standpoint of drain-
age.


Figure O.-Loosely tied tomato plant slipped to ground at base of stake.







Tomato Production


Plastic Mulch
This refers to a method of covering the beds with a polyethy-
lene plastic sheet and then setting or seeding through the plastic.
This method can be used with any of the aforementioned cultural
practices. Although the use of plastic mulches has proved satis-
factory in the production of strawberries, and looks very promis-
ing for tomatoes, sufficient information is not yet available to
warrant a general recommendation of its use in tomato produc-
tion. However, with proper guidance, growers may try it on a
limited scale.
Florida tomatoes are usually grown for either mature-green
or vine-ripe harvest. Mature-green is a term referring to the
practice of harvesting the fruit when fully mature but before
any red color has developed. When picked at this stage the
tomato fruit will normally develop its typical red color after a
few days in a ripening room. It should be emphasized that if
the fruit is harvested before it is fully mature-green, the time
required to turn red is greatly extended, quality is reduced, and
often the fruit will decay before ripening. Premature harvest-
ing often results in a considerable loss to the grower.
The majority of tomatoes for mature-green harvest are
grown with unstaked or ground culture. However, some growers,
using a suitable variety, will stake the plants with the idea of
harvesting either mature-green or vine-ripe, depending on
market and weather conditions.
The production of tomatoes for vine-ripe harvest is relatively
new to the state. Because of the demand of the trade for high
quality fruit this practice is being used quite extensively in
many of the tomato-producing areas of south Florida. In con-
trast to fruit harvested mature-green, tomatoes intended for the
vine-ripe market are grown on plants that are either staked or
trellised and are picked when the slightest red color is visible
on the fruit. Since vine-ripe tomatoes generally are of better
quality, they usually bring a premium price over tomatoes har-
vested mature-green.
Some of the advantages and disadvantages of the various
cultural practices may be listed as follows.

Advantages of pruning and staking or trellising:
1. Fruit mature earlier.
2. Fruit are larger.







Florida Agricultural Experiment Stations


3. Fruit are cleaner.
4. Harvest season may be extended by many weeks, if the
grower wishes to take advantage of a favorable market,
because fertilizer can be readily applied late in the sea-
son.
5. Better spray coverage is obtained, reducing loss from
disease and insect pests.
6. Plants may be spaced more closely when pruned and
staked. A common spacing for such plants is 4 to 5 feet
between rows and 12 to 16 inches between plants, as
compared with 6 to 7 feet between rows and 24 to 36
inches between plants in unstaked fields.
7. Per acre yields are generally higher.
8. A higher proportion of fruit are usually of No. 1 grade.
9. Losses from fruit-rotting diseases are practically elimi-
nated.
10. Crop can be harvested either as vine-ripe or mature-
green.

Disadvantages of pruning and staking or trellising:
1. Production cost is greatly increased because of additional
labor required.
2. Pruned plants seem more susceptible to various physio-
logical troubles than do unpruned plants.
3. Spread of tobacco mosaic and certain other viruses may
become more serious, since they can be transmitted from
infected to healthy plants by the pruners.
4. Fruits are susceptible to sunscald, since they are exposed.

Advantages of wide-row culture:
1. Improved water-control system which maintains water
table at a nearly constant level and provides rapid drain-
age when needed.
2. Production cost is considerably less than conventional
stake culture.

Disadvantages of wide-row culture:
1. Per-acre yields are lower. Although per-plant yield may
be high, this does not usually compensate for the reduc-
tion in the number of plants per acre.
2. Much tillable land is taken up by ditches, etc.







Tomato Production


Advantages of plastic mulch:
1. Weed control cultivation is practically eliminated because
most weeds, except nutgrass and torpedo grass, will not
penetrate the plastic.
2. Losses from fruit-rotting diseases are reduced; this is
particularly important with unstaked tomatoes on old
vegetable farms.
3. Loss of plant nutrients due to leaching rains is reduced.
4. Higher yields are obtained, due in part to reduction of
fruit-rot and in part to maintenance of an established
nutrient environment.
5. Maximum benefit from soil fumigation is obtained when
plastic is laid immediately after treatment is applied.

Disadvantages of plastic mulch:
1. The plastic is relatively expensive and can be used for
only one crop season.
2. Its use requires an initial investment in equipment for
laying the plastic.
3. Additional labor is required to remove plastic from field
at end of the crop season.
4. Its use is limited to level fields since constant water table
is necessary.

It may be seen from the above discussion that the type of
tomato culture to use must be the grower's decision. The various
methods are so intimately associated with the economics of the
crop that no specific recommendations can be made. Recent
figures indicate, however, a higher net return per acre from
staked than from unstaked tomatoes and from vine-ripe than
from mature-green tomatoes. (See Florida Agricultural Experi-
ment Station, Ag. Econ. Mimeo Report 63-8.)

Nutritional Sprays
Both major and minor nutrients can be included in the
pesticidal spray program. Certain of the minor elements are
included in fungicide formulations (zinc, manganese and iron
carbamates, and the copper fungicides). Boron from borax or
Sol-U-Bor and molybdenum from sodium or ammonium molyb-
date can also be included in sprays. Zinc, manganese, iron, and
copper can also be included as sulfate or chloride salts. Chelated







Florida Agricultural Experiment Stations


iron or iron oxalate can be used in the spray mixture. Exces-
sive quantities of soluble nutrients should be avoided; perhaps
not more than 4 to 5 pounds total per 100 gallons.
The soluble salts of major nutrients such as nitrogen, potas-
sium, calcium, phosphorus, and magnesium can also be included
in foliar sprays although this should only be considered supple-
mental to that obtained from the soil and should be used only
when needed because of certain problems (cost, incompatibility,
phytotoxicity) concerning their use. A temporary deficiency or
a non-functional root system may be reason to expect benefit
from foliar sprays. However, minor element sprays and ferti-
lizer minors might be considered interchangeably as fundamen-
tal or supplemental depending on soil and weather factors.
If pH values are maintained above 6.0, especially between
6.5 and 7.0 (as recommended for optimum production), foliar
sprays can be considered as a good source of most of the minor
nutrients because at the above-mentioned pH's, soil minor ele-
ments become less available.

Physiological Disorders
Blossom-end rot was once considered the most injurious
disorder of tomato fruit. However, the basic cause of blossom-
end rot was determined to be a deficiency of calcium, and effec-
tive control of the disorder can be obtained through the use
of proper liming and fertility methods and spraying with cal-
cium chloride.
Crease-stem of tomatoes is easily recognized by a creasing
of the stem near the tip. As the disorder progresses, the creas-
ing often becomes so deep that a hole is formed through the
stem. This disorder may be transitory or may result in a severe
stunting and dwarfing, the growing tip becoming so malformed
that it resembles a "witches broom". Although the cause of
crease-stem is unknown, evidence indicates that it occurs during
periods of rapid growth. Growers should avoid overfertiliza-
tion during the early stages of growth, as this renders plants
very susceptible to this abnormality under weather conditions
favoring rapid growth. Varieties vary in susceptibility to
crease-stem.
Blotchy ripening (graywall, internal browning, or vascular
browning) has been causing losses of considerable magnitude
for several years. Evidence indicates that the disorder is associ-







Tomato Production


ated with low light intensity, high soil moisture, high nitrogen
or low potassium nutrition, tobacco mosaic virus infection, and
excessive soil compaction. Although it has been studied exten-
sively, to date no one has shown how to prevent or control
the disorder under field conditions. The use of resistant varieties
such as Manalucie, Manapal, Indian River, and Floradel will
prevent serious loss of fruit due to the graywall phase of blotchy
ripening. Homestead 24, W. R. Grothen's Globe, and Super-
market are quite susceptible.
Catface is a disorder which occurs to some extent wherever
tomatoes are grown. The extremely malformed and scarred
blossom ends, which characterize catface, are caused by an ab-
normal development of the flower pistils. The factors causing
this abnormal development are not known, and no means of
control has been developed.
Black shoulder is characterized by dark colored fruit
shoulders which are very susceptible to invasion by fungi and
bacteria. Although the disorder is becoming increasingly preva-
lent in Florida, its cause is as yet unknown.
Growth cracking consistently causes heavy f r u it losses.
These cracks may be radial or concentric to the stem end and
may be shallow or deep. They not only are unsightly but also
serve as infection loci for fungi and bacteria. Although certain
varieties such as Floralou, Floradel, Immokalee, Manapal, and
Indian River have some resistance to cracking, no variety has
been developed with sufficient resistance.
Sunscald is common during periods of hot, dry weather and
on green, immature fruit. Any factor such as the leaf-spotting
diseases, the wilt diseases, or excessive soil moisture which
causes loss of foliage and consequent exposure of fruit to the
sun will increase the severity of sunscald. Pickers opening up
the vines cause excessive sunburn. Therefore, the control for
the disorder consists of the avoidance of foliage loss and fruit
exposure.

PESTICIDES
The effective chemical control of tomato diseases, insect
pests, or weeds must be dealt with in two categories: (1) the
selection of the effective pesticide, and (2) the proper applica-
tion of the pesticide. The fungicide must be specific for the
disease, the insecticide for the insect, and the herbicide for the






Florida Agricultural Experiment Stations


weed. The crop also must have a high degree of tolerance to
the pesticide. In most cases several chemicals may be equally
effective, and the choice falls to that which is most economical.
Formulation of the pesticide may also influence its acceptability.
Wettable powders, dusts, granules, and emulsifiable concentrates
are available. Plant growth habit, soil type, time of year, and
the type of pest may all be factors in making a decision as to
which formulation is best suited to a given situation.
Tomato fungicides generally are more effective when applied
as sprays, whereas many insecticides may be applied effectively
as dusts. However, spraying is usually preferred for fungicides
and insecticides, because most of these are compatible when
mixed together and thus may be applied in a single operation
(Figure 11). Herbicides are usually applied as sprays, but some
chemicals are less volatile and incorporate better into the soil
surface when formulated as granular materials.










A






.U -'
Figure 11.-High clearance sprayer showing spray pattern coverage.

Weed Control
With the increasing costs of labor, machinery, land clearing,
and harvesting there is a real need for tomato growers to in-
crease yields and the efficiency of production. The use of plastic-






Tomato Production


covered beds in the production of tomatoes makes the use of
chemical' weed control in row middles a must, since cultural
methods destroy the plastic. Four herbicides now have labeling
and FDA clearance for use on tomatoes. It is suggested that
growers who are not familiar with the use of weed killers
restrict their initial use to a limited field trial unless the
application can be supervised by an individual who is thoroughly
experienced in the use of the chemical to be applied.
Diphenamid has given consistently good results when applied
at planting to direct-seeded tomatoes, at post-setting, or at late
lay-by. Diphenamid must be applied to soil which has normal
moisture and before the weed seedlings emerge. The recom-
mended application of 5 pounds of active ingredient per treated
acre broadcast controls annual weeds and grasses for 8 to 14
weeks. Watergrass (Cyperus sp.) is not controlled by this
chemical. Tomatoes are quite tolerant to Diphenamid, and lay-by
applications to 12 pounds per acre have shown no injury. Spray
which wets the foliage at lay-by application causes no injury or
burning. It has been reported from other areas that this chemi-
cal has a tendency to remain active in the soil for long periods
and has proved injurious to winter cover crops following to-
matoes. No such effect has been observed in Florida, but the
grower should realize this possibility exists.
PEBC (Tillam) incorporated pre-plant or at early lay-by has
given reliable weed control wherever proper application has
been made. Control of annual weeds and grasses lasts for 7 to
9 weeks. Tomatoes have a satisfactory tolerance to this herbi-
cide, and a broadcast rate of 4 pounds (80 pounds of 5 percent
granular) should be made before fruit begins to form. High
moisture is not essential. In fact, if the treatment is incorpo-
rated into dry soil, the herbicide will be more effective than if
the soil is wet.
Solan has proved effective when applied over direct-seeded
tomatoes. The chemical at 4 pounds (4 quarts of 4E) per acre
broadcast is effective against germinated weed seeds, and for
this reason treatment should be delayed until 3 to 4 days after
seed is sown. Moisture is critical. No dry soil layer should exist
if treatment is to be successful. Best results have been obtained
following overhead irrigation. Lay-by treatment at 4 pounds
per acre is also recommended and may be employed in addition
to the treatment following seeding. Solan gives control of weeds
5 to 7 weeks.





























Figure 12.-Row on left had lay-by herbicide treatment at time the plants
were staked. The row on right had no treatment.

Amiben is recommended for use as a late lay-by treatment
at 4 pounds per acre broadcast and has given good control of
weeds for 7 to 8 weeks (Figure 12). The chemical must be
applied pre-emergence to weeds, and soil moisture must be good.
Only the granular formulation is labeled for use on tomatoes,
since the liquid formulation causes some foliage injury. Heavy
rains following treatment may reduce effectiveness.

Insect Control
Insect pests of the tomato are numerous. Perhaps the most
common pests are various cutworms-the black (Agrotis ypsilon
[Rott.]), the granulate (Feltia subterranean [F.]), and others;
aphids of several species; the tomato fruit-worm (Heliothis zea
[Boddie]); the fall armyworm (Laphygma frugiperda [A. &
S.]); the southern armyworm, (Prodenia eridania [Cram.]; the
tomato hornworm (Protoparce quinquemaculata [Haw.]); the
banded cucumber beetle (Diabrotica balteata [Lee.] ; the serpen-
tine leafminer (Liriomyza trifolii [Burgess] and L. munda
[Frick]); and the southern green stink bug (Nezara viridula
[L.]). In some sections mole-crickets, Scapteriscus spp., also
are pests.







Tomato Production


Chlordane in granular form is probably the most widely
used insecticide for the control of soil-inhabiting insects such
as cut-worms and mole-crickets. These insects should be brought
under control before tomato plants are set or before the seed-
lings emerge if the field is seeded directly. It has been found
that 2 to 4 pounds per acre of actual chlordane will control these
insects whether applied in bait form, mixed in the fertilizer
(provided that fertilizer is incorporated uniformly in the surface
of the soil), or applied directly on the ground in a granular
formulation.
Recommended insecticides are given in Table 3.

Disease Control
The principal leaf diseases are (1) gray leaf spot, caused by
Stemphylium solani Weber; (2) late blight, Phytophthora in-
festans (Mont.) dBy; (3) early blight, Alternaria solani (Ell.
& Mart.) Jones and Grout; (4) bacterial spot, Xanthomonas
vesicatoria (Doidge) Dows.; (5) black spot, Phoma destructive
Plowr.; and (6) gray mold, Botrytis cinerea Pers. ex Fr. The
above arrangement is not necessarily in order of importance,
since severity of any one disease depends on a particular set of
environmental conditions.
All spray rates for disease control, unless otherwise indi-
cated, are expressed as pounds of formulated material per 100
gallons of water. Bacterial spot may be controlled under light
to moderate conditions by the use of copper (4 pounds of 48-
53% metallic copper) plus maneb (1.5 pounds). This mixture
gives considerably better control than copper alone. Copper
(4 pounds) will give some control of bacterial spot, and in some
areas the combination of copper (4 pounds) plus streptomycin
(up to 400 ppm) is more effective than copper alone. However,
in certain areas streptomycin is ineffective because of the pres-
ence of resistant races of the bacterium.
Late blight constitutes a constant threat during cool, wet
weather. Maneb (1.5 pounds) gives excellent control of late
blight and should be applied on a 5-day schedule or twice weekly
when the disease is present and the weather favorable. Di-
chlone (0.75 pounds) and zineb (2 pounds) can be alternated
with maneb on gray leaf spot resistant varieties. Zineb (2
pounds) also can be alternated with maneb on gray leaf spot
susceptible varieties.








Florida Agricultural Experiment Stations


Table 3.-Sprays and dusts for the control of insect pests.


Min. days
Pest Spray Dust to Harvest


Aphids


Armyworms,
Tomato fruitworm
Hornworm

Loopers

Leafminers




Stink bugs,
Other plant bugs

Banded cucumber
beetle
Cutworms






Wireworms

Mole-cricket


Dimethoate (Cygon) 2E, 1/2-1 pt.
Parathion 15% WP, 3 lbs.
Thiodan 50% WP, 1 lb.
DDT 50% WP, 2 lbs.
Sevin 50% WP, 2 lbs.
TDE (DDD) 50% WP, 2 lbs.
Thiodan 50% WP, 1 Ib.
Parathion 15%, 3 lbs.
Thiodan 50%, 1 lb.
Dimethoate (Cygon) 2E, %/-1 pt.
Diazinon 25% WP, 1-2 lbs.
Dibrom 8E, 1 pt.
Guthion 25% WP, 1-2 lbs.
Parathion 15% WP, WP, 3 lbs.
Parathion 15% WP, 3 lbs.
Sevin 50% WP, 2 lbs.
Thiodan 50% WP, 1 lb.
Thiodan 50% WP, 1 lb.
Guthion 25% WP, 1-2 lbs.


21
Parathion 2% 3
1
DDT 5% 3
Sevin 5% NTL*
TDE (DDD)
5% 1
Parathion 2% 3
1
21
Diazinon 2% 1
4
3
Parathion 2% 3
Parathion 2% 3
Sevin 5% NTL*
1
1
3


Chlordane 2 lbs. active ingred./acre before planting.
Toxaphene 2 lbs. active ingred./acre before planting.
2% chlordane or 21/ % toxaphene wheat bran bait
before or after planting.
Regular sprays of DDT, TDE, or parathion will
prevent the establishment of cutworms after the
crop is planted.
Diazinon 2 lbs. active ingred./acre before planting.
Parathion 2 Ibs. active ingred./acre before planting.
Aldrin 2 lbs. active ingred./acre before planting.
Chlordane 4 lbs. active ingred./acre before planting.
2% aldrin or chlordane wheat bran bait before or
after planting.


* No time limitation when used as directed.

In past years Botrytis gray mold has caused great damage
on ground crop tomatoes for winter and early spring harvest.
Recent work, however, has demonstrated that effective control
of the disease can be obtained by liming to a pH of 6.5. In
addition the disease can be controlled by spraying gray leaf spot
susceptible varieties with Dyrene (2 pounds) and gray leaf spot
resistant varieties with dichlone (0.75 pounds), ferbam (3
pounds), Dyrene (2 pounds), or thiram (2 pounds). Ferbam







Tomato Production


is adequate under routine conditions, but is inferior to Dyrene
or thiram under severe conditions. Dichlone will give some con-
trol when being used for late blight control.
Ghost spot, an unsightly but otherwise harmless silvery ring
spotting of fruit, is caused by abortive infections by Botrytis.
Hence, control of ghost spot is the same as that given for gray
mold.
Gray leaf spot can be controlled by maneb (1.5 pounds),
zineb (2 pounds) or Dyrene (2 pounds). Certain tomato varie-
ties (see Table 2) possess a high degree of resistance to gray
leaf spot. When these varieties are used, the less expensive
fungicides, thiram and ferbam, can be used for gray mold con-
trol. When gray leaf spot susceptible varieties (see Table 2)
are grown, Dyrene should be used for gray mold control.
For general control of foliage diseases the following com-
binations or schedules can be used: (A) maneb (1 pound) +
Dyrene (1 pound), (B) maneb (1.5 pounds) alternating with
zineb (2 pounds), (C) maneb (1 pound) + thiram (1 pound),
(D) maneb (1 pound) + ferbam (3 pounds), and (E) maneb
(1 pound) + copper (4 pounds). None of these schedules will
give absolute control of all the foliage diseases, and as disease
pressures vary, because of changing weather conditions and
disease prevalence, the adopted schedules should vary.
Maneb + Dyrene will control, under routine conditions, all
the major fungal diseases of tomato foliage and is recommended
especially for gray leaf spot susceptible varieties. If late blight
becomes troublesome, increase maneb to 1.5 pounds; should gray
mold or gray leaf spot become troublesome, increase Dyrene to
2 pounds.
Maneb alternating with zineb will control all the major fun-
gal foliage diseases except gray mold and can be used on both
gray leaf spot susceptible and resistant varieties. On susceptible
varieties a close watch for gray leaf spot must be maintained,
and Dyrene (2 pounds) should be added to the schedule if the
disease becomes troublesome. For gray mold control use Dyrene
(2 pounds) on gray leaf spot susceptible varieties and Dyrene
(2 pounds), thiram (1.5 pounds), or ferbam (3 pounds) for
gray mold control on gray leaf spot resistant varieties.
Maneb + thiram or maneb + ferbam will control, under
routine conditions, the major fungal foliage disease except
possibly gray leaf spot. Both combinations are recommended
for use on gray leaf spot resistant varieties. If late blight be-







Florida Agricultural Experiment Stations


comes prevalent, increase maneb to 1.5 pounds, and should gray
mold become troublesome, increase thiram to 1.5 pounds.
Maneb + copper is recommended for the control of bacterial
spot. This combination also will give fairly good control of the
major fungal foliage diseases except gray mold. The combina-
tion is recommended for use on both gray leaf spot susceptible
and resistant varieties during the months of August through
October, providing bacterial spot is troublesome.
Tomatoes are frequently damaged by diseases known as
viruses. Tobacco mosaic, tobacco etch, cucumber mosaic, pseudo-
curly top, and veinbanding (the potato Y virus) are members
of this group known to be important in Florida. Transmission
of the casual agents is mainly by sucking insects, especially
aphids. Unfortunately, the grower cannot arrange an effective
defense against the introduction of these diseases to his crop
by virus-bearing insects that happen to alight on his plants.
However, he can, under some circumstances, by weekly or twice
weekly use of modern phosphatic insecticides such as parathion,
prevent the sucking insects from propagating on his crop and
thus hold the proportion of virus-affected plants in his crop to
a minimum.
Most of these viruses occur in crop plants other than tomato
and in weeds common in Florida. Therefore, removal of weeds
within and around a'tomato field will aid in curtailing loss due
to virus diseases. Moreover, all crops of tomato, pepper, and
cucumber on which harvest has been completed should be disked
under before the old plants can serve as hosts for aphids that
can fly to a younger tomato crop. Tomatoes planted in a locality
where Irish potatoes are grown are exposed to undue hazard,
because the standard potato varieties can be carriers of viruses
harmful to tomatoes.
Tobacco mosaic is better known and probably causes more
damage than the other viruses mentioned above. Its effect on
tomato is mainly in reduction of fruit quality, but reduction in
marketable yield may be heavy if the plants become infected
when young or if a potato virus occurs in combination with
tobacco mosaic. The virus is readily transmitted by hand, less
readily but to an important extent by machines such as tractors
and sprayers. For these reasons tobacco mosaic is most im-
portant on crops that are pruned and tied. On a ground crop
it may be noticeable on only the rows over which the sprayer is







Tomato Production


drawn. Workers using tobacco should wash their hands thor-
oughly with a strong soap before handling plants.
The worst soil-borne disease is Fusarium wilt, caused by the
fungus Fusarium oxysporum (Schlecht.) f. lycopersici (Sacc.)
Snyder and Hansen. Other diseases, such as (1) Verticillium
wilt, caused by Verticillium albo-atrum Reinke and Berth.; (2)
sclerotiniose, caused by Sclerotinia sclerotiorum (Lib.) dBy; (3)
southern blight, caused by Pellicularia rolfsii (Sacc.) West; (4)
Rhizoctonia diseases, such as damp-off and soil rot, caused by
Thanatephorus cucumeris (Frank) Donk; and (5) bacterial
wilt, caused by Pseudomonas solanacearum E. F. Smith, are
sometimes severe in small areas.
The soil-borne diseases, Fusarium and bacterial wilts, are
not controllable by use of chemicals after the crop is planted.
The varieties W. R. Grothen's Globe, Indian River, Homestead
24, Manalucie, and Manapal are highly resistant to Fusarium
wilt (Race 1) and may be planted on soils known to harbor the
causal agent of this disease. Since no suitable varieties are

Table 4.-Sprays for disease control.

Rate
Disease Fungicide Sprays (lbs/100 gal.)

Bacterial spot Copper, 48-53% + Maneb, 80% 4 + 1
(Xanthomonas vesicatoria) Copper, 48-53% 4

Early blight Maneb, 80% 1%
(Alternaria solani) Zineb, 75% 2

Gray Leaf Spot Dyrene, 50% 2
(Stemphylium solani) Maneb, 80% 1%1/
Zineb, 75% 2

Gray Mold* Dyrene, 50% 2
(Botrytis cinerea) Thiram, 50% 1%
Ferbam, 76% 3
Dichlone, 50% %

Late Blight Maneb, 80% 1%/
(Phytophthora infestans) Zineb, 75% 2
Dichlone, 50% 34

Phoma Maneb, 80% 1%
(Phoma destructive) Zineb, 75% 2

* Plants on soils limed to a pH of 6.5 should not need protection.







Florida Agricultural Experiment Stations


available which have resistance to bacterial or Verticillium
wilts, tomatoes should not be grown on land infested with these
pathogens. It is better not to plant tomatoes or any other sus-
ceptible crop in soil known to be heavily infested with Pellicu-
laria rolfsii, the causal agent of southern blight.
Generally speaking, if one or more of the above-listed soil-
borne troubles are known to be severe in a field, the most satis-
factory cleanup known is to keep all summer growth disked
down for one or two summers, or to plant crops not affected by
the disease organisms present. The clean summer fallow treat-
ment is known to be quite effective in reducing losses from
disease on subsequent tomato crops.
Recommended pesticides for disease control are listed in
Table 4.
For more information on fungicides and insecticides or
fungicide-insecticide combinations see Florida Agricultural Ex-
periment Station Circular S-47 (Compatibility of Insecticides,
Fungicides and Nutrients for Vegetable Crops) and Florida
Agricultural Extension Service Circular 193E (Commercial
Vegetable Insect and Disease Control Guide).

SUMMARY
An attempt has been made in this bulletin to cover all of the
major phases of tomato growing on the sandy soils of Florida.
Certain phases have been more elaborately discussed elsewhere
(see appended list of Florida Agricultural Experiment Station
and Extension Service Bulletins and Circulars).
In weed and pest control, many new pesticides are still under
test, and the recommendations included represent only the best
knowledge available at this time.
For the most part, topics discussed in detail in the body of
this paper are those which are not discussed in bulletin form
elsewhere, but which are known to be of importance because of
the frequency of questions asked. It is suggested that gardeners
and growers who encounter problems not covered herein con-
tact their county agricultural agents or the Florida Agricultural
Experiment Stations.






Tomato Production


REFERENCE LIST OF FLORIDA PUBLICATIONS

Experiment Station Bulletins
457 The Sclerotiniose Disease of Vegetable Crops in Florida
550 Production of Vegetable Plants in Seedbeds on Sandy
Soils
560 Containers for Shipping Florida Tomatoes
652 An Economic Evaluation of Grade and Size Standards
for Mature Green Tomatoes
660 Labor and Material Requirements for Vegetable Crops

Experiment Station Circulars
S-15 Control of Mole Crickets
S-47 Compatibility of Insecticides, Fungicides and Nutri-
ents for Vegetables
S-48 The Value of Soil Testing Kits in Vegetable Crops
Production
S-101 Cause and Control of Blossom-End Rot of Tomatoes
S-147 Marketing Vine-Ripened Tomatoes
S-153 Tomato and Pangolagrass Rotation for Sandy Soils of
South Florida
S-161 Immokalee, a Disease-Resistant Determinate Vine-
Type Tomato with a Concentrated-Yield Potential
S-162 Floradel, A Productive, Large, Smooth Tomato
Adapted for Pink Harvest

Extension Circulars
98B Vegetable Production Guide: Tomatoes
153B Commercial Vegetable Variety Guide
193E Commercial Vegetable Insect and Disease Control
Guide
196A Vegetable Weed Control Guide
225 Commercial Vegetable Fertilization Guide

These publications may be obtained at the office of the county
agricultural agent or by writing the Bulletin Room, Agricultural
Extension Service, Rolfs Hall, University of Florida, Gainesville,
Florida. Single copies are free to Florida residents on request.

























AL E




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs