Circular 96R December 1955
COOPRATMVB EXTEMNION WORK IN
AGRICULTURE AND BOMB ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida.
Florida State University ar d
United States Department of Agriculture, Cooperating
H. G. Clayton, Director
(Prepared by Vegetable Crop Specialists
in cooperation with workers of the
Florida Agricultural Experiment Stations)
Production practices are subject to frequent
changes because of new problems and new ap-
plications of research to meet them. No attempt
is made here to anticipate future problems, but,
instead, the current pertinent facts on watermelon
production are presented. Experienced growers
may want to modify some of these practices for
their specific conditions.
Additional information is available in Univer-
sity of Florida Agricultural Experiment Station
Bulletin 491 and USDA Farmers Bulletin 1894.
For currently available publications and for
further details on local problems, contact your
County Agricultulal Agent of the Florida Agri-
cultural Extension Service.
FLORIDA AND LEADING COUNTIES HARVESTED
ACREAGE (1955 Season)
Alachua .................... 5,800 Levy ................... 4,500
Collier ...................... 2,100 Madison .................... 8000
Columbia ................ 2,200 Marion ...................... 700
Gilchrist .................. 5,200 Pasco ..................... 4,500
Hillsorongh ............ 6,000 Polk .......................... 2,800
Jackson .............. 2,900 Sumter .................... 4,500
Jefferson .................... 2,400 Suwannee ............ 600
Lake ........................ 5,500 All Others ..............22,600
AGRICULTURAL EXTENSION SERVICE
S AV (MI M YIELDS, COSTS, AND RETURNS'
S .'PER ACRE
(Bued on Representative Growers' Records
Area Leesburg Newberry-Trenton
Seasons averaged 1949-50 to 1958-54 1949-50 to 1958-54
Yield per acre
(melons) 296.7 222.6
Production costs $126.41 $ 64.44
Harvesting costs 87.18 24.20
Sales F.O.B. 155.80 91.78
Net returns -7.74 8.09
Planting Dates Days to Maturity
North Florida.f..........i..._MarM April 90 to 100
Central Florid&-.-.._.. January-March
S Cannonball (Black Diamopd, Florida Giant).-
Melons large (82-4A6 lbs.), nearly round. Dark
green, solid color. Seed brownish-black, mottled.
No resistance to common diseases. A standard
Congo.-Melons large (82-40 lbs.), elongated.
Dark green stripes on a green background. Seed
white to light tan. Anthracnose resistant. Sub-
S ject to blossom-end injury. A standard shipping
Fairfax.-Melons medium-large (30-35 lbs.),
elongated. Dark green stripes on a light green
background. Resistant to Fusarium wilt and
Charleston Gray.-Melons medium-large (28-85
lbs.), elongated. Gray in color when mature.
Seeds black, flesh deep red and high in quality.
Resistant to anthracnose and moderately resistant
to Fusarium wilt. Delayed thinning recommend-
ed when planted on wilt-infested (old) land.
Other varieties,--Garrison (very good quality.
No disease resistance. For local market.) Blacklee
(Fusarium wilt-resistant. Good quality. Local
New Hampshire Midget.-A novelty type melon,
8-5 lbs. in isze. Generally inferior to standard
Varieties in quality. No disease resistance. Ma-
tures in 65 to 70 days.
PLANTING PLANTING SEED
DISTANCES DEPTH REQUIRED
Between rows 2 inches Per amre-1 pound
8 to 12 feet (8 plantings)
6 to 8 feet
,... . ..- -----
Type Pounds per Acre
Marl soil ....................................... 6-8-6 550
Light sandy ................................ 6-8-6* 900**
Dark sandy ............... ............... 6-8-6* 900
*A 4-84 may .n uwd roEvied equivalent amoun of natrosen
** Double this amount for the irrigated areas of Immokalee and
Indlantown. To guad aainst leachin tram heay rtain, one-haf
of the after may e applied at plantn t d th other half
Wen runner start to for..
A pH of 5.5 to 6.0 is optimum for watermelon
production on the acid sands. Marl soils and
sands with a pH above 6.0 may require spray
applications on the plants of 11 to 2 pounds of
manganese sulfate per 100 gallons of water where
this deficiency develops.
Top-dressing applications of nitrogen or a com-
bination of nitrogen and potash vary in amount
and frequently according to seasonal conditions.
One to 3 applications at rates equivalent to 100
pounds of nitrate of soda and 25 pounds muriate
of potash per acre generally meet the needs dur-
ing a given growing period.
INSECTS AND CONTROLS
Sprays: Amt. per
Insects Dusts 100 gallon Baits
Aphids, Lindane Lindane 25%,
Melonworm, 1%% 1 Ib.-
Pickleworm, Parathion Parathion 15%,
Leafminers, 1% 1 lb.
Corn earworm Parathion Parathion 159%,
(rindworm) 1% 1 lb.
Cutworms 2% Chlor-
Precautions.-Do not apply any of the organic
insecticides to wet or damp foliage. Applications
in the afternoon reduce chances of injury to bees.
Sprays and dusts made from crude, low gamma
benzene hexachloride should not be used. Insecti-
cides made from Lindane can be used. Do not
use toxaphene, DDT or chlordane sprays or dusts
When using parathion take special precautions
not to spill the insecticides on any part of the body
or to breathe the spray mist, vapor or dusts.
Always read and observe cautions on label.
DISEASES AND CONTROLS
Anthracnose, gummy stem blight and downy
mildew are the major diseases of watermelon that
are controllable by fungicidal spraying or dusting.
The importance of these diseases varies consider-
ably from year to year, depending on weather con-
ditions, but in most years one or more of them
may cause considerable damage to watermelons in
Florida. In dry seasons, especially in North Flor-
ida, there may be little apparent benefit from
spraying or dusting. In general, however, a well-
timed and well-executed spraying or dusting pro-
gram will result in higher yields of higher quality
Inadequate coverage of foliage is probably the
most common cause for failure of fungicidal
spraying or dusting programs. The entire sur-
face of both upper and lower sides of all leaves
should be covered. Because more thorough
foliage coverage is possible, spraying is prefer-
able to dusting and use of a sticker-spreader is
Failure to apply fungicides early enough and
often enough are other common faults. The first
fungicide application should be made at the late
bunching or early running stage of development.
The number and timing of subsequent applica-
tions should be governed by weather conditions.
In dry seasons less frequent applications are
needed. In general, 8 to 5 applications will suffice
in north and central Florida, while 7 or more may
be needed in south Florida.
In the Immokalee area, field observations indi-
cate it may be advisable to start applications
earlier and that more applications usually will be
necessary; nabam is a first choice material until
fruits begin to set.
Anthracnose Zineb 65~., 2 Ibs.
The varieties Congo, Fairfax and Charleston
Gray are resistant to common forms of anthrac-
Downy mildew* Zineb 65%, 2 lbs. Zineb 4-6%%
Copper, 1% lbs, Copper 6-7%
metallic, plus sticker
Copper Is not generally recommended for the West Coat and
Indian River are Copper ia reoommndd in other aas ppdofleall
for downy mildew controL It should not be used prior to frdlt-et
and zineb aplieations should be alternated with t thereafter.
Gummy stem Zineb 656, 2 lbs.
blight plus sticker
Wilt.s-Since Fusarium wilt results primarily
from soil-borne infestation, it cannot be controlled
by the use of fungicides. The use of resistant
varieties or new land are the best control
Even with wilt-resistant varieties (Blacklee,
Fairfax, Charleston Gray) a minimum of 8 years
between crops is recommended. Charleston Gray
should not be planted for 3 or more years following
an extremely susceptible variety such as Cannon-
ball. On land where watermelons have been
planted previously, delayed thinning is recom-
mended with Charleston Gray. With wilt-sus-
ceptible varieties such as Cannonball a minimum
of 8 years between crops is desirable.
There is always danger of wilt occurring on
new land where drainage water from a diseased
field has flowed over the new field, or where cattle
have had access to both fields.
White Heart and Hollow Heart.-Explanations
for the occurrence of white heart and hollow heart
are inadequate. White heart is believed by many
to be a hereditary character expressed only under
certain environmental conditions. Certain varie-
ties and strains appear to be inore resistant than
others to these troubles.
TREATMENTS FOR CONTROL OF SEEDTBORNE
DISEASES, PARTICULARLY ANTHRACNOSE
Ounces per Teaspoons per
100 Pounds Seed Pound of Seed
Chloranil (48 ) ................... 6
Thiram (o0%) .......................... 4
FIELD MICE CONTROL
Zinc phosphide, 8 ounces
Scratch grain, 40 pounds
Soybean lecithin, % pint
(Mineral oil, corn oil, or some other vegetable oil
can be substituted)
First, three to four weeks before planting.
(It may be advisable to also place poison bait in
the area bordering the field to be planted.)
Second, 4 days before planting.
Rate.-One teaspoonful every 15 to 20 feet; 40 pounds
for 10 acres for each application.
When melons are 3 to 4 inches long prune, down
to 1 to 2 melons per vine, depending on local cul-
tural practices. In sandy soils leave only 1 fruit
per vine until the melon is about 6 inches in
diameter; then allow a second melon to form. In
the heavier soils of the state melon vines can
carry 2 melons simultaneously. However, 1 good
melon per vine per season would give growers
higher than average yields.
Sunburning of watermelons can be reduced by
use of a lime paste that is painted on maturing
melons. A mixture of 2 pounds of hydrated lime
in a gallon of water is applied to the exposed sur-
face of the melon with a rag swab or brush. The
application must be made prior to the bleaching
that precedes sunburning; once started, the.break-
down of tissues accompanying sunburn cannot be
stopped. The lime paste can readily be removed
from the melons with a moistened rag.
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