Southeastern U.S. Vegetable Crop Handbook - 2022 - 132

Plant spacing requirements for mini seedless watermelon
are considerably less than spacing requirements for normal seedless
watermelon production. Some mini seedless varieties will
need to be planted close in order to maintain an average size of
7 pounds or less. As little as 10 square feet per plant might be
necessary. For example, if rows are spaced on 6 ft. centers, mini
watermelon plants should be spaced 1 ½ to 2 ft. apart within the
row.
SPECIAL NOTES FOR PEST MANAGEMENT
DISEASE MANGEMENT
Cucurbit Downy Mildew Forecasting System: Cucurbit downy
mildew (CDM) is a devastating foliar cucurbit disease. While
difficult, if not impossible to control, CDM incidence can be
reduced by using effective IPM practices and judicious use of
appropriate crop protectants. A useful tool for evaluating the potential
incidence of CDM is the CDM forecasting system. This
program depends on the accurate reporting of CDM in the field
as well as the monitoring of over 50 strategically placed sentinel
plots. These plots are monitored by Plant Pathologists at multiple
Land Grant Universities throughout the United States and
Canada. Forecasts of the epidemic movement of the disease are
generated 3 times a week. Risk maps are produced from these
forecasts. For forecasts, maps, local contacts, and other helpful
information please visit our website http://cdm.ipmpipe.org. If
you think you have CDM, please contact your local Extension
office.
Fusarium Wilt: Fusarium wilt of watermelon is widespread
throughout the southeastern US. Most varieties of watermelon,
other than many heirloom varieties, are resistant to race 0. Many
seeded (hybrid diploid) and seedless (triploid) varieties are resistant
to race 1. However, there are no watermelon varieties resistant
to race 2. Currently grafting is the only cultural practice
available to manage soils infected with race 2.
All commercial watermelon varieties are susceptible to
race 2, which is present in parts of Florida, Georgia, and South
Carolina. The superscripts " S " for susceptible, " MS " for moderately
sus- ceptible, " IR " for intermediate resistance, and " R "
for resistant are listed next to each recommended variety. These
superscripts indi- cate the reaction of commonly grown diploid
and triploid varieties to race 1 of Fusarium wilt. Growers should
choose resistant variet- ies whenever possible, including the pollenizers
that they select for seedless watermelon production.
INSECT MANAGEMENT
Cucumber Beetle: Watermelons are resistant to bacterial wilt;
however, control may be needed to prevent feeding damage
to seedlings. Treat when an average of two beetles per plant is
found.
Aphids: Aphid feeding can stunt young transplants and delay
fruit maturation. Thorough spray coverage beneath leaves is important.
Treat seedlings every 5 to 7 days or as needed.
Mites: Mite infestations generally begin around field margins
and grassy areas. CAUTION: DO NOT mow or maintain these
areas after midsummer because this forces mites into the crop.
Localized infestations can be spot-treated. Note: Continuous use
of pyre- throids may result in mite outbreaks.
HARVESTING AND STORAGE
See Table 14 for postharvest information.
132
2022 Vegetable Crop Handbook for Southeastern United States
http://cdm.ipmpipe.org
Southeastern U.S. Vegetable Crop Handbook - 2022

Table of Contents for the Digital Edition of Southeastern U.S. Vegetable Crop Handbook - 2022
