Watermelon

Watermelon seed is sown directly once soil has warmed to 60–70°F and all frost danger has passed, planted about ½–1 inch deep in hills or stations spaced roughly 2–3 feet apart with rows 6–8 feet apart, later thinned to one or two strong seedlings per spot. Where the season is short, seed can instead be started indoors 3–4 weeks ahead in plantable pots, hardened off gradually, and set out with minimal root disturbance once seedlings have one or two true leaves.

Plants want full sun and a light, well-drained, loamy soil in the neutral-to-slightly-acid range, with organic matter worked into heavier ground. Moisture must stay consistent from germination through fruit set, since dry spells cause uneven emergence and misshapen fruit, but watering is eased off as fruit nears ripeness to avoid diluting sweetness; drip irrigation and morning watering help limit the foliar disease and weed pressure that come with wetting the leaves. A balanced fertilizer such as 10-10-10 is worked in before planting, with a starter solution applied to transplants.

Because flowers are separate male and female blooms on the same vine, fruit set depends on repeated bee visits to each female flower during its single day of receptivity, so insecticides toxic to bees are avoided or applied only when bees are inactive; cool, rainy, or windy weather that keeps bees away reduces pollination and fruit quality.

Watermelon vines are attacked by a wide range of insects, including mites, squash vine borers, aphids, squash bugs, stink bugs, cutworms, pickleworm, and cucumber beetles, alongside diseases such as downy and powdery mildew, bacterial wilt, fusarium wilt, and anthracnose. A cold-weather stress condition sometimes called sudden wilt can cause vines carrying a heavy load of ripening fruit to collapse almost overnight in late summer, and keeping plants well fed and watered helps limit it.

Poor pollination, heat stress, or excess water can all lead to poor fruit set or misshapen melons, and blossom end rot is a further physiological disorder recorded on the crop.

Ripeness is judged by several combined signs: the tendril nearest the fruit stem turns brown and dry, the ground-contact spot on the rind shifts from pale green or white to yellow, the blossom end softens, and a tap produces a dull, hollow sound rather than a sharper tone. Fruit is cut from the vine with a sharp knife or pruners rather than pulled.

Harvested melons can be held at 45–50°F and 85–95% relative humidity for two to three weeks.

Watermelon is grown as an edible fruit, eaten raw or pickled, with the rind itself edible once cooked; the flesh is also pressed into juice or used in mixed beverages.

Watermelon traces to Sudan, where it was first domesticated and cultivated, with Kordofan melons considered its closest wild relatives and possible progenitors. Wild watermelon seeds recovered from a prehistoric site in Libya date to roughly 3500 BC, and the crop was established in Egypt by 2000 BC before spreading more widely as a table fruit noted in early Hebrew texts.