- UNIVERSITY OF Cooperative Extension Service
ji -"FLORIDA Institute of Food and Agricultural Sciences
A Vegetable Crops Extension Publication
fort.icultural Sicinea Department P.O. 110690 Caincsville, FL 32611 Telephone (352)392-2134
June 10, 1998
I. NOTES OF INTEREST
A. Vegetable Crops Calendar.
II. COMMERCIAL VEGETABLES
A. Tomato Nitrogen Fertilization.
B. Effect of Terminal Growth Removal on Yield of Bell
C. Evaluation of Potato Seedlings for Horticultural
Performance in North Florida, 1997.
SIII. VEGETABLE GARDENING
A. Florida Record-size Vegetables through June, 1998
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 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, age, handicap or national origin.
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I NOTES OF INTEREST
A. Vegetable Crops Calendar.
July 28-30, 1998. 4-H Horticulture
Training Track and Competitive Events. Contact
July 29-30, 1998. Horticultural Events,
State 4-H Congress. Contact Jim Stephens.
II COMMERCIAL VEGETABLES
A. Tomato nitrogen fertilization.
With the increased interest at the state
agency level (DACS, DEP, etc.) in fertilizer
BMPs, particularly nitrogen, we have been
reviewing the Florida fertilizer research literature.
Although the main interest is in nitrogen, we have
been summarizing the research literature for P and
K as well. Summaries for about 10 vegetables
have been completed and several of these
summaries were reviewed recently by an ad hoc
fertilizer working group consisting of IFAS
researchers and Extension personnel, including
The results of tomato fertilizer research is
presented in Figure 1 summarizing response of
tomato yield to N fertilization. Our current
nitrogen recommendation is 175 lb per acre.
Critical evaluation of Figure 1 would make it
difficult tojustify a recommendation of much more
than 200 lb per acre. On finer textured soils, the
maximum N response was often to no more than
120 lb per acre. On very sandy soils an occasional
response to 200 to 220 was observed.
The fertilizer working group agreed that
changing our N recommendation to 200 lb per acre
would make it easier for growers to adapt to any
future interim nitrate management measures while
still generally reflecting the scientific N research
data. Increasing the N rate above 200 Ib per acre
might result in reduced yield as indicated in Table
1. Any changes in our recommendations will have
to pass through the Dean for Extension's Nutrient
Oversight Committee and would probably not take
effect for several months.
Fig. 1. Relative Yield of Tomatoes for Experiments, Years, and Seasons as a
Function of Added N
o [ ; -
0 Csizinszky el al., 1988
X Rhoads et al., 1988
O Csizinszky at al.. 1985
O Rhoads et al., 1988 *
A Csizlnszky et al., 1988
* Rhoads et al.. 1988
+ Clark et al.. 1989 o Clark et al., 1989 Clark et al., 1989
X Hochmuth et al.. 1989' Hochmuth et al., 1989 Shuleret a., 1989"
f 1_o a Shuler et a., 1991 m Shuler et al., 1992 0 Carranza et al., 1996 *
M Rhoads et al. 1996 a Rhoads at al., 1996 Locascio et al.. 1996
-Rhoads, 1997* Rhoads, 1997
Experim nts where 96 to IGo". RY occuned Berween T5il and I( IdOacre N
0 Symbols can overlap.
0 S 100 150 200 250 300
N Rate (lb/acre
350 400 450 500 550 600
(Hochmuth, Vegetarian 98-06)
B. Effect of terminal growth removal on
yield of bell peppers
The terminal growths of flowering
ornamental plants are often removed (clipped) to
enhance flowering and increase market value.
Processed tomatoes and tobacco have also been
clipped for years. For fresh market Bell peppers,
more flowering per plant should produce more
fruits thereby increasing yields. However,
increasing the number of flowers and fruits could
produce smaller, unmarketable fruits. In deciduous
fruit culture, thinning is often required to increase
fruit size. Therefore, while clipping could
potentially increase marketable yields, it may also
produce smaller fruits, more culls and increase
labor and production costs.
The objective of this demonstration was to
evaluate the yields of Bell peppers (Capsicum
annuum L.) after removal of terminal growth. A
farm site was selected in Lee County, Southwest
Florida, for this demonstration.
On November 15, 1997, two rows of
'Camelot' Bell peppers were planted on raised
beds, 8.5 inches apart (between and within rows)
on 36-inch center. On November 19, 1997,
treatments of clipped and controlled unclipped
plants were established. Each treatment consisted
of five replications of 20 plants in a randomized
complete block design. Normal horticultural
practices were employedby the grower cooperator.
Fruits were harvested in February 10, March 3 and
16. Fruits quantities, weights, culls and grades
were determined at time of harvest. Effects of El
Nino precluded additional harvests.
Over three yields, the control yields
surpassed the clippedyields in quantity andweight
on the first picking only (Table 1). There were no
first pick culls and the amount of culls remained at
or below 6.2 percent over the last two pickings.
The marketable yield from the control plots was
3.5 times greater at first picking than yield from the
clipped plots (Table 2). For the second and third
pickings, marketable yields from the clippedplots
were 1.3 and 1.4 times greater thanyields from the
control plots, respectively.
Grades of large and extra-large fruits were
determined over three yields (Table 2A). The
grower did not select for smaller sized fruits. For
control and clipped plots, fruits graded large were
predominant during the first and third picks. For
both treatments, extra-large fruits were dominant
during the second pick. Clipping plants did not
reduce the ratio of extra-large to large fruits. Over
three yields, total marketable fruits, were not
significantly different, 269 and 267 fruits, from
control and clipped plots, respectively. However, if
the trend of higher yields from clipped plants
continued, yields of clipped plants might out
performed yields of unclipped plants.
Early indication are that clipping Bell
peppers reduced first yield but increased successive
yields. Smaller initial yield is a disadvantage for
growers desiring a large volume early in the
season. However, higher successive yields couldbe
adventitious for some growers. Where total volume
is important, clipping Bell peppers might be used
to increase yields.
Table 1. Total quantity, weight and percent cull from yields of control and clipped bell peppers.
Quantity Weight (b) Cull (percent)
Treatment 2/10/98 3/3/98 3/16/98 2/10/98 3/3/98 3/16/98 2/10/98 3/3/98 3/16/98
Control 188 125 66 87.2 59.9 21.0 0 2.4 1.8
Clipped 54 167 81 24.6 79.1 29.2 0 1.8 6.2
Table 2. Size graded of clipped and unclipped bell peppers.
2/10/98 3/3/98 3/16/98 Total
Treatment Large X-Large Large X-Large Large X-Large Large X-Large
Control 70 24 52 70 34 19 156 113
Clipped 18 9 79 85 50 26 147 120
(S. H. Brown & C. S.
C. Evaluation of potato seedlings for
horticultural performance in north Florida,
Atlantic, Red LaSoda, and Sebago were the
standard cultivars, 45 USDA, six Michigan State
University, and six Dutch (Wolfe and Wolfe) potato
seedlings or cultivars were evaluated in a
randomized block design experiment consisting of
fourreplications. Seedlings were planted February
12, 1997, into an Ellzey fine sand with a pH of 5.5-
6.0. Single row 18 ft. long plots were used and seed
tubers weighing approximately 2.5 oz. were planted
8 inches apart.
The field was fumigated January 2 with 6.0
gal per acre in-the row (40 in. spacing) 1,3-D
(Telone II). Aldicarb (Tem i k i1 15G) was applied
at 20 lb per acre at planting. March 11, the crop
was fertilized with 1200 lb 14:2:12 at planting and
side-dressed with 700 lb of the same fertilizer.
Metribuzin (Lexone DF) was also applied at 1.25
lb per acre for weed control. Insecticide and
fungicide applications during the season included
imidacloprid (Provado) at 3.5 oz on March 6;
Bacillus thuringiensis (Dipel 2X) on April 11, 16,
21, and May 1, 16, and 13. Fungicides applied for
late blight control included metalaxyl/chlorothalonil
(Ridomil/Bravo@) 24 fl oz/acre on March 18 and
26, chlorothalonil (Bravo 720) 24 fl oz/acre on
March 21, (Bravo ZN) 34.5 oz/acre on March 24
and 26, (Bravo Ultrex) 1.4 lb/acre on April 4 and
11, Mancozeb (Dithane@ -45) 2.0 lb/acre on
March 29, April 1 and 16, (Dithane F-45) 1.6 qt
on April 8, and maneb (Manex) 1.5 qt/acre April
21 and 25. On May 21 and 23, the vines were
desiccatedwith Paraquat (Gramoxone) applied at
13.0 oz. The crop was harvested, washed, graded
into sizes, and weighdi on June 4 and 5. Tubers
were rated for eye appeal as they were graded and
Vavrina, Vegetarian 98-06)
were scored on a basis of 1 to 10 with 10 being the
greatest eye appeal. Specific gravities were
determined immediately after grading in 15-20 tuber
sub-samples ofU.S. size A tubers, using the weight-
The mean temperatures during February
and March 1997 were 2.6 and 4.0F, respectively,
above normal. During April and May, the mean
temperatures were 4.4 and 3.7F, respectively,
below normal. Heavy rains totaling 10.73 inches
during the last week in April adversely affected
tuber yields, especially the late maturing varieties.
Tuber yields of the yellow fleshed Dutch varieties
ranged from 136 cwt/acre for Fianne to 262 for
Diamant. Diamant and Aziza had tuber yields
equivalent to those of Red LaSoda and both
cultivars also had acceptable appearance ratings.
Their specific gravities (Aziza 1.061 and Diamant
1.071) were lower than the gravity of Atlantic
(1.079). Aziza, Diamant, Estima, and Agria merit
additional testing. The Michigan State seedlings
produced yields less than those ofAtlantic and Red
LaSoda, but equivalent to Sebago. The loweryields
ofthe Michigan seedlings was partially attributed to
late emergence due to dormancy and damage
sustained during the heavy April rains. These
seedlings merit an additional year of testing. The
USDA seedlings havingyields equivalent to Atlantic
were B1312-6, B1317-10, B1318-3, B1319-10,
B1320-6, B1320-10, B1322-13, B1330-3, B1337-
18, B1338-12, B1339-12, and B1342-15.
Unfortunately, eight of these seedlings have been
dropped for further consideration due to poor
performance in Maine during 1997. Clones
maintained for further study include B1322-13,
B1330-3, B1333-18, B1338-12, and B1339-12.
Table 1. Selected yields, specific gravities, and appearance of potatoes, 1997. University ofFlorida, Hastings-
Total size Percent of Specific appearance
Seedling (cwt/acre) Atlantic gravity (1-10)Y
Atlantic 232 100 1.079 6.7
Diamant 262 113 1.071 8.0
Red LaSoda 254 109 1.056 4.7
Aziza 240 103 1.061 8.3
Estima 185 80 1.066 8.0
Agria 184 76 1.058 7.3
Sebago 164 71 1.059 8.0
B1322-13 218 94 1.066 7.0
B1338-12 218 94 1.070 7.3
B1330-3 212 91 1.075 7.3
B1339-12 196 84 1.064 6.7
B1333-18 182 78 1.072 7.3
LSD (0.05) 42 --- 1.6
zMarketable tuber grade sizes.
YTuber eye appear with 10 being highest and 1 lowest.
(Marion White, D. P. Weingartner, Vegetarian 98-06)
III. VEGETABLE GARDENING
A. Florida record-size vegetables
through June 1998.
January is the month for the biggest weigh-
in of large vegetables held in Florida annually. June
is the second biggest weigh-in month, for the
Jacksonville Harvest Fair brings in a new record
each June. The former event is conducted during
opening day of the South Florida Fair in West Palm
Beach. To both events, exhibitors have brought in
by the "roll-it or tote-it" method vegetables ranging
from the lowly radish to the mighty pumpkin. In
south Florida, it is not unusual to see some of the
tropicals, such as cassava, calabaza, boniato,
cocoyams, and true yams along with the radishes
and tomatoes. In Jacksonville one is more likely to
encounter beets, tomatoes, cucumbers, and
zucchinis. The draw there is the cash money being
offered as prizes. Winners in two divisions adult
and youth receive the following: 1t place $200;
2nd place $150; 3rd place $100; 4" place $75; 5t
place $50; and 6h place $25. In Jacksonville the
cash prizes are much smaller ( $35 top prize ).
Entries are weighed in on a scale. Then a
point system is used to calculate an equivalent rating
for all the various items. The system is based on the
average normal size for each kind ofvegetable, and
the degree of difficulty in growing that vegetable to
a large size. As an example, a 1 pound tomato is
equivalent to a 36 pound pumpkin or an 18 pound
watermelon. Some of these fair contest winners
occasionally break the state records. For example,
a giant red beet was weighed in June at 8 pounds,
beating the old record by 3 pounds. The following
is a listing of the current record-holders for
vegetables grown in Florida. Five new records were
set in 1997-1998. These are listed in bold type.
Florida Record-size Vegetables through May, 1998
3kra, pod (wt)
3kra, pod (length)
Early Round Dutch
La. Green Velvet
9 1/2 inches
8 lb. 1 oz.
12 b. 10 oz.
5 lb. 4 oz.
20 lb. 9 oz.
29 lb. 8 oz.
3 lb. I oz.
11 lb. 6 oz.
15 lb. 6 oz.
1 lb. 3 oz.
13 ft. 3 in.
2 lb. 6oz.
4 lb. 7 oz.
4 lb. 8 oz.
I lb. 8 oz.
11 lbs. 2 oz.
21 lb. 8 oz.
19 lb. 8 oz.
18 lb. 3 oz.
80 lbs. 13 oz.
11 lbs. 13 oz.
22 1/4 in.
3 lb. 11 oz.
1 lb. I oz.
2 lb. 13 oz.
30 lb. 3 oz.
3 lb. 12 oz.
23 lb. 5 oz.
36 lbs. 8 oz.
131 lb. 12oz.
23 lb. 12 oz.
3 :b. 11 oz.
47 lb. 9 oz.
11 lb. 11 oz.
6 lb. 2 oz.
18 lb. 4 oz.
12 lb. 15 oz.
(Stephens, Vegetarian 98-06)
Prepared by Extension Vegetable Crops Specialists
Dr. D. J. Cantliffe
Dr. S. M. Olson
Mr. J. M. Stephens
Dr. T. E. Crocker
Dr. G. J. Hochmuth
Dr. S. A. Sargent
Dr. C. S. Vavrina
Dr. D. N. Maynard
Dr. W. WWI
Professor & Editor
Dr. J. M. White