Growing melons in a greenhouse allows the gardener to provide optimal soil conditions, moisture and temperature for the melons to thrive. Greenhouses protect the melons from temperature fluctuations, severe weather and other environmental conditions that can damage growth. The ideal way to grow melons is to train the plant's vines to grow on a support system or trellis, which provides optimal light and air distribution for the growing plants and ensures that only the strongest fruit receive the necessary nutrients.
Observe your melons for small side shoots to develop, generally within two months of initial planting. Allow the shoots to develop for about a week, until they are about 6 inches long.
Test the side shoots to determine which ones are strongest. These may be the thickest, longest or most secure to the main body of the plant. Select the two strongest shoots.
Remove or prune away all but the two strongest shoots to ensure that all the plant's nutrients go toward growing only the strongest fruits.
Wrap the strong shoots around a trellis system. Choose from a variety of trellis systems, including nylon string and wooden stakes. Secure the trellis firmly upright in the ground; as the melons start to grow, it will have to support a lot of weight.
Monitor the vine growth as the plant continues to thrive. The trellised vines will produce smaller shoots, which will produce fruit. Remove any excess flowers or fruit to ensure that each small shoot produces only one melon so you get the healthiest possible fruit from each shoot.
You can allow the melon vines to grow along the ground, but monitor them for higher risk of insect infestation. Maintain the vines the same way whether they grow on the trellis or on the ground.