Watermelon is a fun, quick-growing and delicious garden fruit to cultivate. And when summer temperatures rise, it can be tempting to harvest a few seeds from a cold, juicy grocery store-bout watermelon and plant them in your garden. But most of the watermelons found in grocery stores are hybrids, and the fruit that they produce is largely inedible. To grow delicious watermelons, purchase your seeds from a garden center.
Choose a spot for your watermelons. Watermelons need a lot of room to grow and as much sun as they can get for as long as they can get it.
Prepare the soil. Delicious watermelons need nutritious soil in which to grow. Amend the soil with a six-inch layer of aged organic compost.
Create watermelon hills. Watermelons grow best in raised soil. Create a firmly packed "hill" that is one foot high and a little larger than two feet in diameter. Neighboring hills should be at least six feet away from one another--watermelons need a lot of room to grow.
Sow watermelon seeds in groups of three at the top of each hill, one half inch into the soil. Most likely, only one seed in each group of three will survive. If more than one survives, cut the weaker one with a pair of pruning shears. Pulling it will disturb the other seedling's fragile root system.
Water your watermelon seeds so that the hill is moist, but not soaking.
Spread two to three inches of organic mulch on the mound, but do not cover the seedlings.