How To Grow Watermelon

Planting Watermelon

Watermelons prefer soil with plenty amounts of manure or compost. Grow in full sun in well-drained soil. Thrives in the heat. Direct sow seed in the garden about 2 weeks after last frost when the soil is warm. If you have a short season, you can also start indoors in peat pots and then plant in the garden after the last frost. Seed Depth: ½ – 1" Plant Spacing: at least 18" apart Row Spacing: 8' apart Watermelons need lots of room to grow. We always plant our watermelons in hills with about 2 seeds per hill (after thinning) with the hills about 8' apart. Fertilize regularly and keep the soil moist at all times. They like lots of water. And be sure to keep weeds down. Allow 7-14 days for germination.

Harvesting Watermelon

There are several ways to tell when watermelons are ready to harvest. Methods we've tried include observing when the underside turns from white to yellow, the stem near the base of the fruit dries up and shrivels, melons stop growing, and using the "thump" method that should sound hollow and dull. Have you heard the ole' timers method with the straw? Take a piece of straw, set it crossways on the melon, and if it turns to line up with the melon, it is ripe!

Saving Watermelon Seeds

Pollinated by insects. Suggested isolation distance is ¼ mile unless barriers such as barns or tree lines may allow for shorter distances. Harvest the melons when they are ready to eat, save the seeds out and rinse with water to clean. Allow seeds to dry on a paper plate. Seeds should remain viable for 4-5 year if kept cool and dry.

Common Problems

  • Bacterial Fruit Blotch
    Seedlings will develop dark, oily lesions that can die rapidly. Infected fruit will have dark splotches on the upper side of the fruit. This disease spreads quickly, causes the rind to rupture and fruit to rot. Melons with light green rinds are more susceptible, whereas, darker green rind are more resistant. Minimize handling of the seedlings and avoid working in the fields when they are wet. Purchase healthy seeds or plants. Destroy diseased plants immediately.

Suggested Companions

  • Potatoes
  • Salsify
  • Lamb's Quarters
  • Sow Thistle

Poor Companions

  • Tall growing veggies (watermelons need lots of sun)