Find Out When to Harvest Watermelon

Learn When to Pick Watermelons

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Watermelons are at their best when they are fully ripe, juicy and sweet. But how do you know when to harvest watermelon? A good gardener can look at a few things to determine when to pick the watermelon.

When to Harvest Watermelon

Here are a few some indicators that it's ready to harvest:

  • The tendrils near where the watermelon meets the stem, which are normally bright green, will turn brown.
  • The surface of the watermelon goes from shiny to dull.
  • The side of the melon that rests on the soil will turn from green to yellow.
  • It should have a symmetrical body shape and the underbelly of it should be the color of a buttery yellow.
  • When you knock on it with your knuckles it should give off a dull, hollow sound. Not all make the hollow sound, so if it does not sound that way, it does not necessarily mean that the watermelon is not ready to harvest.
  • Watermelon should be ready about 80 days after it is planted. At about the 75-day mark, start keeping your eye on it to see if it is ripe.

More Tips on Growing Watermelon

Now that you know how to harvest a watermelon, here are some additional tips for growing them:

  • Make sure to sow seeds 1-inch deep into the ground and keep them watered well until they germinate. If the weather is cooler when you plant seeds, cover them with black plastic to keep the soil warm. (You can also start the seeds a few weeks before they are expected to be planted in the garden.) Note: Watermelon seedlings do not transport well.
  • Place them in an area with plenty of extra space, as the vines can extend about 20 feet in length. Add a nitrogen-rich fertilizer. 
  • Hills allow better drainage and warm soil for the plants, and it is vital especially when growing watermelons in heavier soils that don't drain well. The hills should be a few inches high and be six to 12 inches in diameter. Plant four or five seeds planted about 1-nch deep in each hill. 
  • The general rule of thumb is to put eight to 10 seeds in a hill, and keep hills three to four feet apart--with at least 8 feet between rows. In each hill, thin plants to the three best ones.
  • When the soil gets dry, water it one to two inches every seven to 10 days.
  • Cover the soil with mulch or gently use a garden hoe it to prevent weeds.
  • Plant three seeds in 3- or 4-inch peat pots or large cell packs. They should be sown about a half-inch deep and put under lights so they germinate. (You can use a seedling heating mat if needed in order to keep them warm.) Seedlings should stay at about 80 F.