/ UNIVERSITY OF Cooperative Extension Service
SFLORIDA Institute of Food and Agricultural Sciences
A Vegetable Crops Extension Publication
Vegetarian 99-09 September 1999
GOE_ ON THE WEB!!!
This epiember issue will be fhe lasi printed
version of Mhe Vegeftrian NewslefHer.
VEGETABLE CROPS CALENDAR
2000 Florida Postharvest Horticulture Institute and Industry
S Save Fertilizer and Improve Water Quality by Using Plant Sap
S More on PLU Numbers
SEvaluations of Sweet Corn Variety Trial
S Offseason (Summer) Management of Vegetable Land
S Sweet Onion Variety Trial, Spring 1999
Planting Depth as a Growth Stimulant
# Plug Transplantsfor Strawberry Crop Establishment in Florida
Horticulture Events at 1999 4-H Congress
Note: Anyone is free to use the information in this newsletter. Whenever possible, please give credit to
the authors. The purpose 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 Insntute oi Food and Agricultural Sciences is an Equal Employment Opportunity Affirmative Action Employer authorized to provide research, educational
Luormation and other services only to individuals and institutions that function without regard to race, color, sex, age, handicap or national origin.
(IrnPFR ATTVF EXTENSION WORK IN AGRICULTURE. HOME ECONOMICS, STATE OF FLORIDA, [FA5, UNIVERSITY OF FLORIDA,
VEGEARIN NESLETERAluuust 1999
GOES ON THE WEB!!!
This September issue will be
the last printed version of the
Vegetarian Newsletter. At the Vegetable
Agent In-Service in Live Oak in August, vegetable
extension faculty and specialists gave several
convincing reasons for making this "upgrade" to our
issues will not be delayed by "snail-mail",
we won't be restricted to 8 printed pages of
articles and will be able to incorporate color
images and graphics,
the material will be in electronic format to
facilitate use by agents
significant savings in printing/mailing will be
During the upcoming months we will be fine-
tuning our new look to be as user friendly as possible.
We will also begin archiving previous issues for
access from the site. I want to thank Susie Futch,
Senior Secretary for extension, and Tami Spurlin,
Computer Support Specialist, Horticultural Sciences
Department, for their creative assistance in making
this transition possible.
So, beginning with this issue, you will be able
to access the Vegetarian Newsletter via our link at the
home page of the Horticultural Sciences Department.
Find the "new" Vegetarian Newsletter at:
Please contact me if you have any questions
Vegetable Crops Calendar
2000 Florida Postharvest Horticulture Institute and
Institute March 6th, University of Florida, Gainesville,
with video-links to several sites in Florida.
Industry Tour- March 7-10th Statewide
For more information contact: Steve Sargent, (352)
392-1928 ext. 215, e-mail sasa~qnv.ifas.ufl.edu or
Abbie Fox (352) 392-1928 ext.235, fax (352) 392-
5653, e-mail email@example.com
1999 Meeting of Florida State Horticultural Society.
Oct. 31-Nov. 2. Stuart, FL.
Save Fertilizer and Improve Water Quality by
Using Plant Sap Test Meters
1,800 Acres of vegetables are being produced in
central Florida with the aid of plant sap test
They cost about $350 for each nitrogen and
potassium plant sap test kit. Growers can measure
nitrogen and potassium concentrations in their
vegetable plants in about ten minutes right in the
field and know exactly whether they need to apply
the next sidedress application of fertilizer to their
crops...or not. Average savings of one sidedress
application per season are being reported a
savings of about $30 per acre or $54,000 per year
for the farms using plant sap meters in Central
Florida. Several growers who used the meters on a
weekly basis to grow sweet corn and watermelons
reported exceptionally high crop yields, in addition
to the fertilizer savings.
The environment wins too 72,000 pounds
of nitrogen and potassium fertilizer were not applied
because growers knew the exact amount of these
nutrients in their crops and that they didn't need
more. That means a lot less chance of excess
fertilizer leaching into the ground water during
irrigation cycles or rainfall. It takes a lot of energy to
produce fertilizer energy savings means less
imported oil and more independence for American
farmers and consumers.
Over-fertilization can cause a lot of
problems for your plants and the fruits you harvest
from them. It can reduce vegetable crop yields by
increasing salt concentrations around the root zone
and stressing the plant. Postharvest quality of
vegetables can be hurt too. Here are just a few
1. Excessive nitrogen increases graywall and
blotchy ripening in tomato.
2. Excessive potassium reduces fruit size and
firmness in strawberries.
3. Excessive nitrogen enhances leaf and tip
burn in lettuce.
4. High nitrogen increases soft rot in potato
Extension agents and crop advisors can
improve field diagnosis of plant problems by
knowing the nitrogen and potassium content of the
2 August 1999
plant. Nitrogen is the mineral element used most by
plants and it is the most readily leached from soils.
Potassium is the next most used mineral element in
plants and has important roles in water potential,
photosynthesis, and respiration. When growers are
convinced that these elements are in adequate supply
they can more readily focus on the remaining
scenarios with confidence that they are being steered
in the right direction.
Agents doing work with vegetables who would
like to be part of the Nutrient and Water Management
Action Team, a subgroup of FL107 SMP, please
contact Richard Tyson (407-665-5554) or Dr. Marion
(Tyson, Multi-county Agent, Vegetarian 99-09)
More on PLU Numbers
In the June Vegetarian (99-06), some PLU
(product look-up) numbers were given which apply to
some greenhouse vegetables. The list given was
incomplete and could be misleading to some in the
industry. For example, by looking at the listed vine
ripe number (4805), a person might assume there is
only one number assigned to vine ripe tomatoes. In
reality, the code listed is assigned to small vine ripe
tomatoes. There is also a PLU code for large vine
The Produce Electronic Identification Board
(PEIB) administers the generic numbering system for
UPC and PLU codes for the produce industry. A
complete list may be obtained by purchasing the
PEIB's most recent edition of "A Guide to Coding
Fresh Produce" from Produce Marketing Association,
P. O. Box 6036, Newark, DE 19714-6036 or call 302-
Thanks goes to Eboni Wall, Division
Assistant, with Produce Marketing Association (PMA)
for this additional information. Before you have PLU
labels printed, double check to make sure you have
the correct number for the product!
(White, Vegetarian 99-09)
Evaluations of Sweet Corn Variety Trial
Florida is the nation's leader in the production
of fresh market sweet corn. In 1997-98, there were
14,225,000 crates (42 Ib) produced on 41,300 acres
for a value of $106,825,000.
A supersweet sweet corn variety trial was
conducted at Long and Scott Farms, Lake Jem, FL, in
the spring of 1999 growing season. The trial was
limited to cultivars/breeding lines of the gene type
homozygous shrunken-2 (sh2), i.e., supersweet.
Yellow, white, and bicolor entries were requested from
seed companies and were included in the trial.
Seeds were planted into an Immokalee fine
sand with hand jabbers on March 11. Plots were
single-row, 2.5 ft wide x 25 ft long with 9-inch in-row
spacing. Four replications were arranged in a
randomized complete block design.
Cultural practices, provided by the
cooperating grower, were comparable to the routine
practices used by commercial growers to produce
sweet corn in central Florida.
One row per variety was harvested by hand
at maturity, beginning May 26 and ending May 28.
Only marketable first ears and/or marketable
second ears were harvested. Individual plots were
harvested only once. Ears were counted and
weighed; sub-samples of 10 marketable ears per
plot were randomly selected, husked, and evaluated
for length, width, maturity, tip fill, husk cover, and
kernel color (Table 1).
Sweet corn yields, expressed as 42-lb
crates/acre, ranged from 200 to 299 crates/acre.
The highest yielding entry in the trial was Novartis'
GSS 0966-VP at 299 crates/acre. Ear length
ranged from 6.8 inches (Florida XP-7 and
R100MVP VAIL-VP) to 7.7 inches (Billy R and
Prime PLS-VP). Ear diameter had some variability.
Three lines were 1.8 inches and three lines were
significantly smaller at 1.7 inches.
Husk cover was variable, with the majority
being acceptable to excellent. The most consistent
excellent-length husk cover was exhibited by GSS
0966-VP and by Florida XP-7.
Flags were variable, with most of them
medium to long (>3 inches). Tip fill was uniformly
excellent. The overall best line evaluated in this test
was GSS 9866-VP from Novartis.
In a similar test last year, Florida XP-7 had
a similar yield, but several lines were significantly
higher. Bandit, Ice Queen, Morning Star, and three
numbered lines were the top performers on sandy
soil. Seed company interest in sweet corn
evaluation on sandy soils in central Florida is not
sufficient to support the test as evidenced by the
lack of company participation in 1999. Future
direction for this program is open and support is
solicited. (cont. on pg. 3)
Table 1. Sweet corn variety trial Lake Jem, FL Spring 1999.
Days to Yieldlacrez Husk Tip Kernel Avg. ear' (inches)
Entry Source maturity cratesy cwt covers Flagsw fill color length diameter
GSS 9866-VP Novartis 78 299 a 125 a L VL 5.0 Y 6.9 c 1.7 b
R100MVP VAIL-VP Novartis 78 236 ab 99 ab V VL 5.0 W 6.8 c 1.8 a
BSS 1605-VP Novartis 78 213 b 89 b V V 5.0 B 7.2 b 1.7 b
Prime PLS-VP Novartis 76 211 b 88 b VL VL 5.0 Y 7.7 a 1.7 b
Billy R AMSA 74 200 b 84 b VL VL 5.0 Y 7.7 a 1.8 a
Florida XP-7 Agrisales 75 200 b 84 b VL VL 5.0 Y 6.8 c 1.8 a
zMean separation in columns by Duncan's Multiple Range Test, 0.05 level General Linear Models Procedure. Means follows by the same letter are not significantly
YYield expressed as 42-lb crates/acre.
xHusk cover: S = short (ears protrudes from husk); M = medium (acceptable); L = long (ear tightly wrapped and completely covered); V = variable; VS =
variable- mostly short; VL = variable mostly long.
wFlags: S = short (less than 3 inches); M = medium (3-5 inches); L = long (greater than 5 inches); V = variable; VS = variable- mostly short; VL =
variable mostly long.
Tip fill: 0 = at least 1 inch of unfilled kernels at the ear tip; 5 = full at tip.
UKemel color: B = bicolor; W = white; Y = yellow.
'Measurements on husked ears, an average value of a 10-ear sample/replication.
(White, Vegetarian 08-99)
Offseason (Summer) Management
of Vegetable Land
A drive-by survey of over-summering practices for managing
vegetable land was conducted in Palm Beach and Martin Counties from
late June to mid-July, 1999. Approximately 8,000 acres (85+% of the
cultivated acreage) was surveyed. There were a total of 78 different farm
locations managed by 19 different growers (16 locations were not
surveyed). Full-bed plastic mulch culture was practiced on 60 different
farm locations by 14 different growers (approximately 6,625 acres
devoted to pepper, tomato, eggplant, squash, cucumbers, etc.). Open
bed culture was practiced on 18 farm locations by six different growers
(approximately 1,375 acres devoted to Chinese vegetables, herbs, sweet
corn, and gladioli). Acreages for over-summer practices and culture
methods are shown in the following table.
(Shuler, Extension Agent IV, Palm Beach County, Vegetarian 99-09)
Over-Summer Practice Full-bed Plastic Open-bed Culture
Mulch Culture (ac) (ac)
Disk 62.5% (4,120) 53.4% (740)
Cover crop z 22.4% (1,480) 44.7% (615)
Over-summer old spring 9.4 % (620)
plastic for fall second crop
Flooded 2.7% (180)
Weeds 2.1% (140)
Mowed 0.6% (40)
Summer crop production 0.2% (15) 1.5% (20)
Total 100% (6,595) 100% (1,375)
z The cover crop used most frequently was a sorghum/sudangrass
hybrid; there were very small acreages of sesbania.
VEGETARIAN NEWSLETTER August 1999
Sweet Onion Variety Trial, Spring 1999
Sweet (short-day) onions are a relatively
minor crop in Florida. Production exists as both dry
bulbs (mature) and green tops (immature). Limited
production exists throughout the state. One of the
biggest deterrents for increased production is
competition from established markets from the
south Texas and south Georgia areas. However,
the potential exists for expanded production,
especially in the areas of local sales and direct
The objective of this trial was to evaluate
the performance of sweet onion varieties under
north Florida conditions.
The transplants for this trial were produced
from field beds at the NFREC, Quincy. Twenty four
entries were seeded on 7 Oct 1998. Seed were
planted at rate of about 30 seed per ft into rows
spaced 12 inches apart. Preplant fertilization of
seedbeds was 30-40-401bs/a of N-P20-K2O.
Dacthal 75 W at 9 Ibs ai/a was applied over the top
after seeding. Seedbeds were top-dressed once
with 34 lbs N/a. Entries were transplanted into the
production field on 15 Dec 1999. Soil type was an
Orangeburg loamy fine sand. Preplant fertilization
was 60-80-80 lbs/a of N-P20s-K20. Production
scheme was 3 rows spaced 15 inches apart under a
5 ft tractor and in-row spacing was 5 inches (62,726
plants/a). Goal 2XL at 0.5 Ibs ai/a was applied on
soil surface before transplanting and Dacthal 75 W
at 9 Ibs aila was applied over the top after
transplanting. Nitrogen was applied twice during
the season at 50 lbs N/a each time. One top
dressing of K20 as KCI at 60 Ibs/a was made
during the season. Registered pesticides were
applied as needed to control pests.
Entries were harvested as they matured,
where mature was defined as when about 25% of
the tops of an entry had fallen down naturally.
Bulbs were lifted, allowed to dry for a few hours,
and tops and roots removed. Bulbs were then
placed in bushel baskets and dried for 72 hours at
1000 F in large drying rooms. After drying time was
complete, onions were removed, allowed to cool
down and graded. Grading consisted of discarding
culls (small onions, splits, off color and decayed)
and sizing into medium (1.5-2 inches), large (2-3
inches) and jumbo (>3 inches) categories. Bulbs
were then weighed and counted.
Harvest occurred from the period of 21 April
to 13 May. Total yields ranged from 1145 50 Ib
bags/a for 'SSC 6361' to 209 50 Ib bagsla for 'Linda
Vista'. No other entry produced yields as high as
'SSC 6361'. Yields were excellent in 1999 except
for the late entries due to several rain storms near
harvest time. 'SSC 6361' produced the largest
bulb at 16.5 oz and 'DPS 1041' produced the
smallest at 8.4 oz. Percent marketable bulbs
ranged from a low of 30.0% for 'Linda Vista' to a
high of 96.7% for 'RCS 1919. Percent bolting level
was very low (<1%) on all entries.
Table 1. Onion variety trial, Spring 1999. NFREC, Quincy.
Entry Source Days from Yield Avg bulb Percent
transplanting (50 Ib sacks/a) wt (oz) marketable
D. Palmer 129 547 de
9.9 i-k 94.6 a-c
Entry Source Days from Yield Avg bulb Percent
transplanting (50 Ib sacks/a) wt (oz) marketable
Chula Vista Petoseed 146 475 ef 10.6 g-j 84.9 a-d
Granex 33 Asgrow 149 466 ef 15.1 a-c 58.5 f-i
DPS 1041 D. Palmer 129 456 ef 8.4 k 92.6 a-c
Yellow Granex Sunseeds 149 378 fg 12.2 e-h 61.9 f-h
Evita Shamrock 149 346 f-h 13.3 b-f 44.6 i-I
SXO 1503 Sunseeds 149 336 f-h 12.6 d-g 55.4 g-j
Daybreak Shamrock 149 330 f-h 11.3 f-i 78.1 c-e
Pegasus Asgrow 149 286 gh 13.3 c-f 40.6 j-l
Dessex Sunseeds 149 243 gh 13.6 b-f 47.3 h-k
Sunsweet Sunseeds 149 209 h 12.1 e-h 35.9 kl
Linda Vista Petoseed 149 209 h 12.8 c-g 30.0 I
z Mean separation Duncan's Multiple Range Test, 5% level.
(Olson, Vegetarian 99-09)
Planting Depth as a Growth Stimulant
In March and July articles we discussed
vegetable crop growth stimulation by means of
biostimulants (chemicals) and biologicals
(organisms), respectively. While both of these
methods boast documented successes, the benefits
of use may not always out weigh the cost of
application. Florida growers, who establish their
crops from transplants, have long enjoyed an
environmental manipulation used to increase plant
growth and yield. That environmental manipulation
is simply ... plant it deeper!
In the early 1990s the standard planting
depth for tomato and pepper transplants in Florida
was to a level between the cotyledons and the root
ball. However, several years of research at the
University of Florida showed a positive linear
increase in plant growth and yield occurs with
incremental increases in planting depth (Fig. 1).
The phenomenon appears to occur across
cultivars, seasons, geographic areas, irrigation
methods, and cultural practices in Florida in general
(Vavrina et al., HortScience, 1994, 1996). Further
unpublished work has shown the technique to be
effective with watermelons, but without the yield
enhancement. But, additional vine cover and faster
development have associated economic benefits as
It seems apparent that planting transplants
deeper also works well in other areas of the United
States. Hanna et al. (HortScience, 1997) have
confirmed similar findings for fresh market tomatoes
(University of California) have seen increased
growth and some yield enhancement in processing
tomatoes (personal communication). Benefits
derived from this environmental manipulation
extend beyond growth and yield as research from
Massachusetts (Mangan et al., Proc. Stand Estab.
Conf., 1996) showed that deeper planting of
processing cherry pepper reduced plant lodging and
Miller et al. (JASHS, 1969) found more uniformity in
cabbage head size with deeper planting in Virginia.
Unfortunately, while passing attempts to
explain this phenomenon have been made, no
studies have documented the mechanisms)
involved. But in the mean time you can put this
cost-effective technology to work for you, just plant
Tomalo response to various planting depths
atl 15 days post transplant.
VEGETARIAN NEWSLETTER August 1999
Plug Transplants for Strawberry Crop
Establishment in Florida
Strawberries in Florida are typically planted
using bare root transplants. These bare root plants
are typically established by applications of overhead
irrigation from 7 to 10 days for up to 8 hours a day.
(Irrigation periods will vary depending on weather
conditions and plant health.) This irrigation
represents approximately 1/ of the total water usage
for the entire strawberry season. In addition to the
heavy water usage associated with establishing
bare root transplants, other difficulties exist. These
difficulties include relatively high plant mortality
rates and problems often related to overhead
irrigation such as nutrient leaching, increased weed
pressures, and disease dissemination.
The use of plug transplants for strawberry
establishment has the potential for addressing many
of the problems associated with the use of bare root
transplants. Research conducted the past two years
at the University of Florida, GCREC, Dover
Strawberry Lab has indicated several advantages of
using plugs. First, plugs can be established using
only drip irrigation, eliminating the need for
overhead irrigation and dramatically decreasing
water usage. For example, in the 1998-99 season at
Dover, approximately 800 gallons of water per acre
were applied through drip irrigation the first two
weeks to establish the plug plants. For contrast,
approximately 600,000 gallons of water per acre are
typically used by growers in this same time period
using overhead irrigation. Second, plant health
defined by characteristics such as root dry weight
and leaf number was significantly better for plugs
than for bare root plants. This improved plant health
apparently led to the third advantage of using plugs,
greater early yield. In the 1998-99 season, early
yields (totals from November and December) with
plug transplants were 140 flats per acre higher than
yields from bare root transplants. Prices received
for strawberries during these months are about
three times higher than prices received later in the
Unless (or until?) water restrictions force
growers to use plugs for transplanting strawberries,
the primary motivation for using the plugs will
naturally be economics. Plugs currently cost nearly
twice as much as bare root plants. This is a
tremendous cost to incur unless the grower is
convinced the up front investment has a good
chance of increasing overall profits. However, the
economic incentive may already be great enough.
Primarily, the increase in early yield can generate
economic advantage. Other economic advantages
of using plugs may include: possible reductions in
disease or weed pressures by not using overhead
irrigation for crop establishment and labor reduction
by not having to replant as many transplants due to
lower mortality rates.
The use of plugs for crop establishment of
strawberries has potential to be a tremendous tool
for increasing profitability as well as conserving
water resources. In the coming season, a
demonstration project will be conducted on five
farms in Hillsborough County. Each farm will have
one-quarter acre of plug transplants and one-
quarter acre of bare root transplants which will be
directly compared for yield, disease and weed
pressures, water use, and certain plant
characteristics. In addition, John Duval (our new
horticulturist at the Dover Lab) will be evaluating the
effects of planting dates on yield and other
parameters using both plugs and bare root plants.
Economic evaluations will be made using data from
both of these projects as well as the data from the
first two years of this plug project. These projects
will allow us to more accurately evaluate the
potential of using plugs for strawberry establishment
and to estimate how they might best be used in
commercial production. This information can then
be used by growers to evaluate how plugs can best
be used by them to maximize their farm's
profitability and sustainability.
(Waldo, Multi-county Agent, Hillsborough County,
Horticulture Events at 1999 4-H Congress
Our 4-H horticulture committee composed of
Bob Black, Jeff Williamson, and myself conducted
three plant science events for the 4-H'ers at
Gainesville during State Congress, the week of July
26-30, 1999. The following are the results.
1. Horticulture Leadership Track. We
provided two days of classes on various
topics related to horticulture. Some of the
class topics covered such things as: writing
a garden record book; lawn mower safety;
plant bonsai; insect eating plants; container
culture; lake watch; and butterfly gardening.
Over 40 4-H members attended. State 4-H
specialist Joy Jordan assisted us with this
event. Instructors were agents, Ray Zerba,
Linda Landrum, Charlie Fedunak, and Bob
Renner, along with the specialists.
2. Plant Demonstrations. Both team and
individual demonstrations were heard and
judged by Heather Miller, Mark Gal, and
Plant Demonstration Results:
1st Pebbles Fullford
2"" Jackie Lundy
3rd Kyle Smith
4th Travis Nettles
5t' Crystal Baker
and Tariea Cox
Awards trip: Pebbles Fullford was selected
to represent Florida 4-H at the national competition
at the NJHA convention, Tampa, Nov. 5-6, 1999.
3. Horticultural Identification and Judging
The Marion County team was selected to
compete at NJHA convention in November. Hendry
County placed second, followed by Volusia at third
(Stephens, Vegetarian 99-09)
Extension Vegetable Crops Specialists
Daniel J. Cantliffe
Professor and Chairman,
Horticultural Sciences Department
Timothy E. Crocker
Betsy M. Lamb
Donald N. Maynard
Stephen M. Olson
Mark A. Ritenour
Ronald W. Rice
Steven A. Sargent
Professor and Editor
William M. Stall
James M. Stephens
Charles S. Vavrina
V/EGETARZAN NE WMETIER