Watermelons are cold-tender, summer vegetable plants that grow best in sandy loam soils and warm temperatures. They are trailing vine plants that are annuals and produce large fruits that are often 30 lbs. or more. Many different kinds of watermelons exist, some of which require a much shorter growing season than others, making them suitable for colder climates where summers are short. Seedless watermelons are also available as sterile hybrids. Watermelons are simple to grow, as long as the plants receive plenty of warmth and room to grow.
Water your watermelon plants deeply and thoroughly to moisten the soil down to and around the roots only during prolonged dry spells or droughts. During extremely dry periods, water the plants once or twice per week.
Keep the soil around the watermelon plants free of weeds by hand pulling or shallowly hoeing the weeds. Check for weeds at least once each week.
Treat your watermelon plants for infestations of cucumber beetles by applying an appropriate insecticide. You can prevent cucumber beetle infestations by using row covers and allowing the covers to remain until the watermelon plants start to bloom.
Harvest your watermelons when the curly light-green stems near the watermelons begin to dry out and turn brown. Ensure that the watermelons' skin feels rough and firm, as well as that the bottom of the fruit has turned from light green to yellowish in color.