INSTITUTE OF FOOD AND
UNIVERSITY OF FLORIDA
A Vegetable Crops Extension Publication
Vegetable Crop DcparLment 1255 DSPP Gaincsville, FL 32611
- Telephone 392-2134
March 15, 1988
I. NOTES OF INTEREST
A. Vegetable Crops Calendar.
II. COMMERCIAL VEGETABLES
A. Fertilizer Expressions Explained.
SB. Leek Variety Demonstration.
SIII. PESTICIDE UPDATE
A. IR-4 Red Alert
IV. VEGETABLE GARDENING
SA. Using mushroom compost in the vegetable garden.
Note: Anyone is free to use the information in this
'. newsletter. Whenever possible, please give credit to the
The use of trade names in this publication is solely for
the purpose of providing information and does not
Necessarily constitute a recommendation of the product.
The Institute of Food and Agricultural Sciences is an Equal Employment Opportunity Affirmative Action Employer authorized to provide research,
educational information and other services only to individuals and institutions that function without regard to race, color, sex, or national origin.
P iR"ECO 'tATI/e "rVTMrirk1 Mht Hhin fl skiav I "M a ri nr- A&r enert I ^t A fthriinafi CTAfTi Mr rf i tl rll A IrAc I killK COCITV M C
S-C I" O
I. NOTES OF INTEREST
A. Vegetable Crops Calendar.
April 29, 1988. State FFA Vegetable
ID Finals, JWRU, University of
Florida, Gainesville. (Contact Jim
May 5, 1988. State Vo-Ag Teachers
Training School, Gainesville.
(Contact Jim Stephens).
May 26, 1988. Home Horticulture
Agent In-Service Training,
Gainesville. (Contact Jim Stephens)
June 20-24, 1988. 4-H Horticulture
Institute, Camp Cloverleaf.
(Contact Jim Stephens).
July 26-27, 1988. 4-H State
Congress, Vegetable (Horticulture)
Contest and Career Exploration,
Gainesville. (Contact Jim Stephens).
II. COMMERCIAL VEGETABLES
A. Fertilizer Expressions
There are several statements or
expressions that Extension faculty
often hear from growers or salesmen
that really need to become teachable
moments. While you can make your
own lists of such expressions, here
are a few from our list.
Statement: "I have an active
fertilizer program. I apply 20
units per ton."
What the grower is trying to
say is that the fertilizer dealer is
billing him for 20 units of some
nutrient (which one?) in each ton of
fertilizer that the grower received.
The grower MUST understand that he
should be paying for pounds of that
nutrient per acre. It is this rate
of application that determines
whether or not the crop has been
properly fertilized. Growers who
talk in units per ton are missing a
fundamental point in their
understanding of fertilizer
Statement: "I like to take the
fire out of my potassium by applying
it in the fall for a winter or
spring potato crop."
As the fire goes out of the
potassium, the potassium goes out of
the soil. The grower who applies
potassium fertilizer in the fall for
a spring planting in Florida's
sandy, low exchange capacity soils
is losing that nutrient to leaching
rains. This statement has been
verified by soil test experiments
under field conditions. Put the
fertilizer on just before your crop
will be using the nutrient. This
practice minimizes exposure to
Statement: "I fly on nitrogen
about a week before I harvest my
watermelons. This application make
'em cut red."
Application of nitrogen at this
time most often results in leaf
die-back. Some of the nitrogen may
enter the melons, increasing the
probability of hollow heart and
whitening of the central tissues
(white not red). There are no
research data to support quicker
maturation of melons, magical gain
of weight, or beneficial changes in
internal tissue color.
Statement: "I need a 2:1 ratio
of potassium to nitrogen in my
This theory started many years
ago with tomato as a way to reduce
blotchy ripening. The research on
which this theory is based is
extremely fragmentary. There is no
supporting work for other vegetables
such as pepper or watermelon. In
fact, take a second to think about
this "theory". It is based on
"hydroponic" logic and really
doesn't apply to our soils in
Florida because in many situations,
there is a lot of potassium in the
soil already. So what's so magical
about a 2:1 ratio in these cases.
The important aspect that we must
teach is to supply the amount of
nutrient needed (from soil or
fertilizer) and not worry about
these magical ratios.
Statement: "I apply foliar
fertilizers to supplement my already
sound fertilizer program because my
plants need "pick-me-up" snacks."
This is an extremely
wide-spread practice in Florida that
adds increased costs to producing
vegetables. Research shows no
response to foliar nitrogen,
potassium, and phosphorus. Only in
some rate situations has research
showed a response to foliar
micronutrients. These include the
alkaline marl and rockland soils in
winter where some micronutrients can
be "fixed" in the soil. Growers
already apply many nutrients such as
copper, manganese, zinc, and sulfur
to the leaves of the plants by the
pesticides. There is much research
data that shows reductions in yields
by "shot-gun" foliar fertilizers.
Growers should conduct tests
(collect actual yield data) to prove
to themselves the value of foliar
fertilizers. Remember, these
materials do represent extra cost
and the negative side might be
reduced yields and the build-up of
micronutrients in the soil to toxic
(Hanlon, Hochmuth, Veg. 88-03)
B. Leek Variety Demonstration.
Leeks are one of the specialty
vegetables being evaluated at the
Gulf Coast Research and Education
Center in Bradenton for possible
commercial production in west
central Florida. To further
evaluate the potential for
commercial leek production, a farm
demonstration was established in
Plant City in the fall of 1987.
Transplants, seeded on July 29
and grown by Plants of Ruskin in
080A Todd planter flats, were set in
the field on September 28.
Thirty-plant plots of 7 varieties
were replicated four times. Plants
were spaced 3-inches apart in the
row on raised beds on 2-foot centers.
Cultural conditions were those used
by the grower.
The leeks were harvested on
January 29, about 180 days after
seeding and 120 days after
transplanting. Some minor plant
loss occurred so that final stand
varied between 27 and 30 plants per
plot. Plot yields varied from 8.7
to 12.3 Ibs with a strong
association between yield and plant
height. Average plant weight was
0.424 lb for 'Tivi', the largest
variety and 0.307 lb for 'Conqueror',
the smallest variety. 'Kilima'
produced the longest shanks whereas
'Alaska', 'Conqueror' and 'Electra'
had the shortest shanks. Highest
yielding varieties had blue-green
leaves whereas the varieties with
lower yields had blue foliage.
Several of these varieties had
performed well in previous trials at
GCREC and growers may wish to include
trial plantings to compare them with
varieties currently being grown.
Cooperators in this trial were
R. L. Mitchell, J. P. Gilreath and
P. R. Gilreath.
LEEK VARIETY DEMONSTRATION Plant City (1987-88)
-- ~ -, i .Obnr
(Maynard Veg. 88-03)
III. PESTICIDE UPDATE
A. IR-4 Red Alert.
Through a memo from Charles
Meister, I have received a
publication "IR-4 Red Alert"
reregistration update 88:1. IR-4
estimates that 25-50% of the
existing registrations for minor
uses could be lost as a result of
EPA's mandated reregistration
program due to lack of adequate
residue data for chemical/crop
IR-4 would like to determine
which registered uses are still
The National Agricultural
representatives are in the process
of listing exactly which
registrations their respective
company will defend.
Charles Meister has asked that
if you feel any of the following
uses are needed, please provide that
input to him.
I am only listing those
chemicals on vegetables here. For
more information please contact Dr.
Chemical: Acephate (Orthene)
Crops: Bean (including lima bean),
celery, lettuce (crisphead).
Chemical: DDVP (Vapona)
Crops: Radish (greenhouse) lettuce
(greenhouse), tomato (greenhouse and
postharvest), cucumber (greenhouse),
Chemical: Fenbutatin-oxide (Vendex)
Crops: Cucumbers (greenhouse).
Chemical: Methiocarb (Mesurol)
Crops: Corn (fresh and popcorn),
pepper (grown for seed),
agricultural crops (pre-plant
application -- crops must be
Chemical: Oxamyl (Vydate)
Crops: Carrot, ginger, potato,
onion (including garlic), celery,
Chemical: Oxydemeton methyl
Crops: Potato, cabbage, bean vines
and hay, pea vines, eggplant,
pepper, melon, pumpkin, squash,
strawberry, and corn (fresh and
Chemical: Dodine (cyprex)
Chemical: Folpet (phaltan)
Crops: Garlic, leek, shallot, onion
dry and green), celery, lettuce,
tomato, cucumber, melon, pumpkin,
squash (summer and winter), and
Chemical: Mancozeb (Dithane M45 and
Crops: Carrot, potato, onion,
celery, fennel, tomato, cucumber,
melon, summer squash, corn (fresh,
field, popcorn), asparagus.
Chemical: PCNB (terraclorR)
Crops: Potato, garlic, lettuce,
broccoli, brussels sprout, cabbage,
cauliflower, bean, pepper, tomato,
Chemical: Dalapon (Dowpon)
Crops: Potato, corn, bean vine and
Chemical: Diphenamid (Enide)
Crops: Potato, pepper, and tomato.
Chemical: Paraquat dichloride
Crops: Potato, turnip, bean vine
and hay, pea vine and hay, tomato,
cucumber, melon, summer squash, corn
(field and fresh).
Chemical: Prometryn (Caparol)
Crops: Celery, corn.
Chemical: Propham (Chem-Hoe)
Crops: Lettuce, spinach, lentil,
Chemical: Trifluralin (Treflan)
Crops: Potato, corn, mustard seed,
Note: This information was based on
EPA's Guidance for the Reregistration
of Pesticide Products Containing
(the Chemical) as an Active
(Stall, Veg. 88-03)
IV. VEGETABLE GARDENING
A. Using mushroom compost in
the vegetable garden.
We all know the benefits of
using home-made compost, chicken,
cow, and other animal manures as a
source of organic fertilizer for the
vegetable garden. Now, gardeners in
Northwest Florida, in the vicinity
of Tallahassee and Quincy have
another organic material available
for use in home gardens. It is
called "spent" mushroom compost, a
by-product of a mushroom growing
facility called Quincy Farms, near
The Quincy plant has been good
for Gadsden County for a number of
reasons more jobs and a demand for
poultry manure and wheat straw from
local farmers. Now it is providing
an additional benefit to the
surrounding community in the form of
organic compost as potential
fertilizer and soil amendment.
Since mushrooms are fungi
instead of green plants, they cannot
use sunlight to make their own food.
Instead, they must grow on decaying
organic matter, such as animal
manure supplemented with straw,
fertilizer and other ingredients,
which is called compost. Since new
compost must be prepared and used
with every new crop of mushrooms,
considerable amounts of the
so-called "spent" compost become
available for disposal.
In a report by Leon County
agent David Marshall (Tallahassee
Democrat, Dec, 1987), spent compost
is readily available for vegetable
gardens from Quincy Farms, near
Attapulgus, Georgia. Quincy Farms Trials by the Georgia Extension
produces fourteen tractor-trailer Service, conducted by Darbie
loads every 3 days. The compost is Granberry and gardener Dan Evorts,
for sale at the farm, but only in showed the compost has promise as a
large quantities. According to soil amendment. Combined with an
Marshall, 4 cubic yards (about a application of fertilizer, the
dump-truck load) sells for around compost gave impressive results.
$30.00. Delivery of large-truck A Wakulla garden supply dealer
loads (50 cubic yards each) may be had the compost tested by IFAS
arranged at around $90.00 plus $1.50 (Greenhouse and Potting Mix sample)
per mile. In addition, several and found it to contain the
middle-men suppliers are offering following in ppm: phosphorous (30);
smaller quantities for sale at sites potassium (3,400); calcium (610);
around Northwest Florida and even as magnesium (204); nitrate nitrogen
far away as Atlanta, where it sells (10); soluble salts (10,290); and pH
for about 10 cents per pound in (7.4).
bags. Plans are underway with
How beneficial is the compost Extension agents in North Florida
in the vegetable garden? So far, counties to test the compost with
the relative few who have used it and without additional fertilizer,
report good results. Still, we in in demonstration vegetable gardens.
the Extension Service need to learn
more about the material before we (Stephens, Veg. 88-03)
can tell others how to use it
Prepared by Extension Vegetable
Crops Specialists 1/ fl/ i A' /
Dr. D. J.
Dr. S. M. Olson
Dr. D. N. Maynard
Mr. J. M. Stephens
Dr. G. J.
Dr. D. D. Gull
Dr. W. M. Stall