/ UNIVERSITY OF Cooperative Extension Service
F LORIDA Institute of Food and Agricultural Sciences
A Vegetable Crops Extension Publication
Horticultural Sciences Department P.O. 110690 Gaincavillc, FL 32611 Telephone 904/392-2134
October 19, 1994
I NOTES OF INTEREST
A. Vegetable Crops Calendar.
I. COMMERCIAL VEGETABLES
A. Evaluating the Impact of Transplanting Depth on Tomato
IIL PESTICIDE UPDATE
A. Section 18 Exception Renewed for Cobra Applications to
Fresh Market Tomato and Green Pepper Row Middles.
IV. VEGETABLE GARDENING
I .,. A. Vegetable Gardening Survey Palm Beach County.
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
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L NOTES OF INTEREST
A. Vegetable Crops Calendar.
November 1-4, 1994. Cucurbitaceae
94. Radison Resort, South Padre Island, TX.
Contact James R. Dunlap, TAES, 2415 East
Hwy 83, Weslaco, TX 78596-8399.
December 6, 1994. Gadsden Tomato
Forum, Sawano Club, Quincy, FL, 9am-lpm.
Contact Ben Castro, Gadsden Co. Extension
II. COMMERCIAL VEGETABLES
A. Evaluating the Impact of
Transplanting Depth on Tomato Yield.
The following was presented at the
1994 Florida Tomato Institute in Naples,
Florida on September 7:
This study was designed to analyze the
effect of transplanting depth on fresh market
staked tomato yield under subsurface seepage
irrigation and polyethylene mulch culture in
Tomato yield (mature green) increased
with increasing planting depth at first and third
harvest, and in combined harvest total yield
(Table 1). A 26% increase in 25 lb boxes of
fruit was realized at first harvest by planting
transplants to the first true leaf, when
compared to just covering the root ball. With
all harvests combined, plants transplanted to
the first true leaf showed an 18% increase in
total yield. Tomato transplants planted to the
cotyledon leaf produced yields intermediate to
the root ball and true leaf plantings.
When breaker and red fruit were
included in the yield totals a similar pattern
emerged (data not shown). Planting tomato
transplants to the first true leaf resulted in
significantly more 25 lb boxes of fruit at first
harvest and in combined harvest total yield
when compared to just covering the root ball.
Planting transplants to the cotyledon leaves
also resulted in larger total yield than root ball
Extra-large fruit volume was increased
at first harvest by deeper planting (Table 2).
Extra-large fruit production was greater for
deeper plantings at third harvest and in
combined harvest total yield, but was not
sufficiently great to result in significant yield
increases. The volume of extra-large fruit,
when expressed as a percentage of the total
yield of fruit at either first or combined
harvest, was similar across all treatments (79 -
81% at first harvest, 72 75% from combined
Average fruit weight was not affected
by planting depth at any particular harvest, but
was significantly greater when considered over
all harvests. Practically speaking however, an
increase in 0.2 of an ounce per fruit may not
be of commercial value.
Greater yields from deeper transplant
depth measured in the fall in SW Florida may
be the result of improved temperature
conditions for root growth. Deeper plantings
may place tomato roots in a cooler
environment with fewer radical temperature
swings. White (1937) showed the optimum
temperature for good root growth is 68-91F.
Root growth slows in temperatures of 95-
104F and practically ceases at temperatures
greater than 104F. This factor could be of
considerable importance in late summer and
early fall plantings grown under plastic mulch
where soil temperatures often exceed 100F
(Vavrina, 1994). Other explanations for
increased yields with deeper planting may
include earlier fertilizer and water acquisition,
and reduced transplant shock from wind
displacement. Additional roots sprouted along
the main stem of the tomato may be of some
importance. Research under drip irrigation in
Quincy, FL showed similar results.
For further information on this trial
please contact Charles Vavrina, SWFREC, PO
Drawer 5127, Immokalee, FL 33934.
Table 1. Tomato Planting Depth Effect on Mature Green Fruit.
First Second Third Total
---------- 25 lb boxes/A-----
First True Leaf 679 a 336 a 888a 1903 a
Cotyledon 603 ab 350 a 779 ab 1731 ab
Rootball 503 b 358 a 701 b 1562 b
Table 2. Tomato Planting Depth Effect on Extra-Large Fruit.
First Second Third Total
----------25 lb boxes/A ---------
First True Leaf 534 a 214 a 630 a 1378 a
Cotyledon 483 ab 237 a 559 a 1279 a
Rootball 408 b 247 a 511 a 1166 a
(Vavrina, Vegetarian 94-10)
I. PESTICIDE UPDATE
A. Section 18 Exemption
Renewed for Cobra Applications to Fresh
Market Tomato and Green Pepper Row
A Section 18 emergency exemption
was approved for the use of Cobra Herbicide
(lactofen) in fresh market tomato and green
pepper row middles to control parthenium and
nightshade. The exemption will remain in
effect until September 1, 1995.
Cobra Herbicide may be applied pre-
and/or post-transplant as a directed, shielded
spray in a spray volume range of 20-50 gallons
A maximum of two ground
applications will be allowed. The first
application will be pretransplant,
preemergence at a rate of 0.3 to 0.5 lb a.i./A
(19 to 32 fl oz/A). The pretransplant
application is to be made to row middles a
minimum of 10 days before transplanting for
both peppers and tomatoes.
The second application is post-
transplanting. For the second application,
tomatoes must be at least 16 inches tall.
Peppers must be transplanted at least 45 days
prior to a post-transplant treatment. Spray
must be directed at the tomato and pepper row
middles (away from the tomato and pepper
plants with minimal contact to the plastic). Do
not apply to dry areas of field. A 30 day PHI
will be observed.
A maximum of 5000 acres of row
middle green peppers and 10,000 acres of row
middle tomatoes may be treated throughout
This is the third year this use has been
requested under section 18 of FIFRA. In
accordance with regulations governing section
18 of FIFRA, if a complete application for
registration of a use which has been under a
specific exemption for any three previous
years has not been submitted, it shall be
presumed that reasonable progress towards
registration has not been met. EPA has
reconsidered the 3-year standard set forth in
the regulations and concluded that, although it
is reasonable in most cases, it may be
unrealistic for many IR-4 minor food uses due
to the programs limited resources and
consequent backlog. Therefore, in evaluating
progress toward registration, the agency will
exercise its discretion in determining whether
or not reasonable progress has been made on
IR-4 minor food use. Generally, IR-4 minor
food uses will be judged against a 5-year
standard, as opposed to the 3-year standard
for all other uses.
According to IR-4's status report,
analysis of tomato samples were to be
completed by the end of May 1994. The
projected due date for submission of a
tolerance petition for the use of lactofen for
green peppers and tomatoes is the first quarter
of 1995, which is within the 5-year limit set
forth for submitting a completed registration
application. Based on this information, it
appears that progress toward registration of
this use has been adequate. However, if a
tolerance petition has not been submitted by
the first quarter of 1995, any future requests
for this use must discuss in detail the progress
toward registration made during the year and
reasons for delay if the tolerance petition has
not yet been submitted. EPA advises that it
will only grant repeat section 18's in the
absence of progress toward registration if
unusual circumstances warrant it.
(Stall, Vegetarian 94-10)
IV. VEGETABLE GARDENING
A. Vegetable Gardening Survey -
Palm Beach County.
My thanks to Gene Joyner, Extension
Horticulture Agent in West Palm Beach, for
sharing the results of a gardening survey he
conducted during a routine public gardening
meeting in 1992. Many of you agents find
such information useful in preparing annual
reports and planning programs for
Table 1. Information about the respondents to the survey.
Sex Age Housing Housing
Male (18) <21 (1) Condo (2) Condo (1)
Female (17) 21-30 (3) House (26) Lot (4)
Total (35) 31-40 (8) Apt. (2) Acreage (4)
41-50 (9) Mobile home (1)
1. First time vegetable gardeners: (8).
2. Experienced vegetable gardeners: (23).
3. Ave. number of years out of last 5 with a garden: (3).
4. Container gardens: (17).
5. Most popular container vegetables: tomatoes, peppers, lettuce, herbs, (strawberries).
6. Approximate size of garden: 14 ft long x 10 ft wide (140 sq ft).
7. Number adding soil amendments: (26).
8. Frequency of amendments used: peat moss (20); animal manure (17); topsoil (16);
sawdust (2); compost (4); vermiculite (2).
9. Number pre-treating soil for nematode control: (13).
10. Fertilizer usage: liquid (14); dry (13).
11. How garden is started: seeds (16); transplants purchased (15).
12. Vegetable seeds, in order of preference: tomatoes, peppers, radish, cucumber, herbs, beans,
carrots, onions, lettuce, eggplant, okra, broccoli.
13. Vegetable transplants, in order of preference: tomato, pepper, herbs, onions, strawberries,
parsley, cucumbers, okra, beans.
14. Irrigation: hand (22); sprinkler (18); drip (4).
15. Vegetable use: fresh (25); frozen (10); dried (1); can (0).
16. Number people eating the vegetables per family: two (70); three (8); four (3); six (2).
17. Number using Extension recipes: yes (2); no (24).
18. Number using printed Extension gardening info: yes (25); No (4).
19. Number attending Extension programs before: (28).
20. Estimated cost of your gardening items (averaged):
Seed ($13.71) Weed control ($74.10)
Transplants ($18.60) Fungicide ($17.90)
Soil amendment ($38.80) Insecticide ($20.65)
Fertilizer ($22.90) Nematode control ($12.20)
21. Average cost per garden: $85.05.
22. Was cost justified? Yes (20); No (7).
23. Number growing garden for fun: (17); for food (9).
24. Most aggravating problems encountered: insects, weeds, animal pests.
25. Most frequently used insecticides mentioned: sevin (16), malathion (8), and Bt (4).
26. Most frequently used fungicides mentioned: captain (5), maneb (4), copper (4),
(Stephens, Vegetarian 94-10)
Prepared by Extension Vegetable Crops Specialists
Dr. D.J. Cantliffe Dr. G.J. Hochmuth Dr. D. N. Maynard
Chairman Professor Professor
Dr. S.M. Olson Dr. S.A. Sargent Dr. W.M. Stall
Assoc. Professor Assoc. Professor Professor
JMr. MStephens Dr. C. S. Vavrina Dr. J. M. White
Professor & Editor Asst. Professor Assoc. Professor