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How to Grow a Large Watermelon

By Cleveland Van Cecil
Giant watermelons can be grown with the right amount of space.
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Watermelon is a warm-season vegetable that, according to the Ohio State University Extension, is thought to have come out of Africa. Watermelons come in several varieties, including large versions. It is possible to push the limits of your watermelon plant to grow giant specimens. There are several competitions across the country where this is done as sport. Growing watermelons in the right conditions with the help of fertilizers is often enough to grow gigantic watermelons.

Choose a watermelon cultivar that will produce large varieties. According to Kevin Philips of the Wilcox County Georgia University Extension, Carolina Cross can grow specimens over 200 lbs.

Locate an area in the garden that receives full sun and has well-draining soil. Build a small hill of soil.

Work 10 lbs. of 10-10-10 fertilizer into the soil around a 5- to 6-foot area around the hill.

Plant the seeds 1 inch deep in the hill. Water as soon as the seed is planted. Keep the soil moist, but not wet during the germination process.

Apply liquid 20-10-20 fertilizer to the hill every week at the base of the plant to increase growth until the watermelon blooms. Switch to 20-20-20 fertilizer every week once the watermelon blooms. Add 3 lbs. of 32 percent nitrogen fertilizer to the soil once the melon vines begin flowering in addition to the liquid fertilizer.

Pick one of the first flowers to bloom on the vine once the eighth and ninth flowers have appeared. Brush this male flower onto the female flowers, which appear after the first six or seven flowers are on the plant. This encourages fruiting.

Spread 1 inch of mulch onto the top of the hill and place the melon you wish to make giant onto the mulch. This protects its belly.

Water the plant once a week.


Things You Will Need

  • Hoe
  • Watermelon seed
  • Fertilizer
  • Mulch