Watermelon
Citrullus lanatus (Syn. Citrullus vulgaris, Colocynthis citrullus)
Tarbooj (Hindi); Hindwana (Pashtu); Tarbooz (Dari/Persian); Habhab (Ethiopia)
Watermelons can provide a valuable alternative to drinking water in desert areas and
in other situations where water is in short supply. The edible portion, which
constitutes about 60% of the whole fruit, contains about 94% water and very little
protein or fat. They do however provide about 7% total sugars, some Vitamin A and
about 5–8 mg/100 g Vitamin C, but are generally more useful as a cash crop than as
a source of nutrition.
They originated in the sandy, dry areas of the Kalahari in Africa and are now
grown on every continent except Antarctica, normally for local consumption. They
are one of the most ancient cultivated crops; Egyptian art shows them being grown
more than 4000 years ago.
There is great variation within the species, from small, hard, bitter and inedible
fruits to the well known large, juicy, sweet fruits. A large number of named
varieties, including hybrids (some of which are seedless), are available, with
improved disease resistance and tough rinds for long distance transport.
The plant is an annual, a member of the Cucurbitaceae (gourd) family, with
trailing stems up to 5 m long. The plants are both self-pollinated and cross-
pollinated, mainly by honey bees. They are monoecious—the male and female
flowers are on the same plant, but they are separate. Seedless fruit production is
discussed on page 243.
Watermelons are related to the Chinese Watermelon or Wax Gourd,Benincasa
hispida, which produce fruits shaped like melon or cucumber up to 40 cm long.
Farmers and other growers can save their own seed, selected from the most well
adapted plants and fruits. The seed should remain viable for two years if kept dry
and cool. To collect seed, the fruits should be left to mature on the plant, then left
about two weeks after harvesting before removing the seeds. These should then be
washed in clean water and dried in the sun.
PLANTING
Propagation: by seed, normally planted in situ into their final station. If
transplanted, great care is needed to avoid disturbing the rootball. Hand pollination
assists fruit setting.
Soil: watermelons prefer fertile sandy loam, near neutral pH (classified as “tolerant”
to soil acidity) but will also grow in a wide range of well-drained soils. Sandy
riverbanks are ideal.
Fertilisers: in common with the other Cucurbits, watermelons benefit from manure
and compost. Inorganic fertiliser, particularly those that are high in Phosphorus, are
also often applied. Nitrogen top dressings should be applied when the plants start
making runners and/or when they start flowering or after fruit-set.
264 TONY WINCH
Melon d’eau, Pasteque (French); Sandia (Spanish); Melancia (Portuguese);
Wassermelone (German); Cocomero (Italian); Kalitangi (Umbundu, Angola);