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How to Grow Melons in a Greenhouse

By Lauren Wise ; Updated September 21, 2017

Melons are a great addition to any family's homegrown diet, as well as to greenhouses. Whether you are growing honeydews, cantaloupes or watermelons, they take their time maturing and crave warmth. Plant the melon seeds in the greenhouse between mid-April and the end of May.

Plant the melon seeds in 6-inch-deep pots, pushed about 1/2 inch into regular potting compost. Lightly sprinkle water over the seeds to make the soil moist. The seeds need to be in full sun in the greenhouse for about 8 hours a day.

Keep an eye on the seeds until they germinate and there are about two small leaves from each sprout. Until this time, water when you feel the soil is moderately dry.

Water the melons with a drip irrigation method, if possible. If it is not, you need to keep in mind that you must water the roots without the plant getting wet. Carefully water right at the roots. It is important to keep the soil moist but never soaking wet, as over-watering will cause melons to split.

Create a line of support for the growing melons, like a single line of string that is tied to the ground by the melon. String this tightly right by the germinating sprout of the melon.

Tie the strongest shoot from the growing melon to the support once it is several inches tall, and pinch out the side shoots that grow from the main stem. This will help the plant promote the most growth in the fruit area.

Keep an eye on when flowers begin to pop up on the melon plant. Once this happens, you need to pollinate the flowers. Do this by taking a small paintbrush and lightly brushing each flower. Three days after this, remove all the flowers that do not have a tiny melon growing behind it (these are the male flowers).

Remove the surrounding leaves around the melon fruit once it is a little larger than a tennis ball. From here on, feed the melon plant once a week with a liquid tomato fertilizer.


Things You Will Need

  • Melon seeds
  • Greenhouse soil trays
  • Standard potting compost soil
  • Water
  • Drip irrigation system
  • Organic tomato fertilizer
  • Support line