This heat-loving, vining plant needs plenty of space to spread out before it produces its delicious fruit.
Watermelons range from single serving types to mammoth fruits that can feed an entire little league team. These vining plants need some room to sprawl, though some newer varieties feature more compact growth for small space gardens. All thrive in areas with long, hot summers, and will reward your patience with their juicy, garden-fresh fruits.
Plant watermelon seeds when weather is warm and nighttime temperatures regularly stay above 50 degrees F. Watermelons like full sun and rich soil. Place seeds in slightly rounded hills 2 feet in diameter and 5 feet apart. Sow 5 to 6 seeds 1 inch deep in a small circle on the top of each hill. When seedlings have several sets of leaves, thin them to the 3 strongest plants in each hill.
If you're starting seeds indoors, plant several weeks before your last frost date. Sow seeds in individual pots of seed-starting mix. Keep the pots warm and moist and provide a strong light source until weather warms enough to transplant the seedlings outdoors.
Watermelon Care Must-Knows
Watermelons grow best in long, hot summers. If summers are short or cool, consider laying black plastic over the soil for insulation. Make several holes in the cover to allow moisture to reach plant roots. If insect pests are a problem, consider covering young plants with row covers. Remove the row covers when watermelon vines begin blooming as row covers prevent pollination. Water young plants regularly to encourage good growth and fruit development. Reduce watering as fruits ripen for the best sweet flavor.
Watermelons will not ripen off the vine. Experience helps in determining when to pick them, but there are several cues to help you figure out when to harvest. Each melon has a curly tendril near its stem end. This tendril turns brown when the fruit is ripe. The spot where the melon rests on the ground usually turns from white to creamy yellow as it ripens. And a ripe melon gives a dull thump when tapped with your knuckle.
More Varieties of Watermelon
This variety produces 15- to 25-pound round melons that are light green with dark green stripes. The flesh is dark red and firm. Plants are resistant to anthracnose and fusarium wilt.
Citrullus lanatus 'Jubilee II Hybrid' offers oblong green-striped fruits that have red flesh and grow to 30 to 40 pounds. It has excellent anthracnose and fusarium wilt resistance. It is especially well suited to the Southeast.
'Moon and Stars' is heirloom named named for the yellow splotches on the dark green rind. One or more large golden patch makes up the "moon" and numerous smaller dots are the "stars." The flavorful red-fruited melons weigh 25 to 40 pounds.
This type features round, deep green fruits that have a thick rind that resists cracking, red flesh, and weigh 8 to 10 pounds each. The plants are compact, stretching only 3 to 4 feet long.
'Sweet Beauty Hybrid' bears 5- to 7-pound fruits that are a good size for small families or gatherings. The sweet red flesh has superior flavor. Fruits are borne on semi-upright vines that grow up to 3 feet tall.
Citrullus lanatus 'Tiger Baby' bears striped round fruits that weigh 7 to 10 pounds. The pinkish red flesh is dens and sweet. It has good resistance to fusarium wilt.