When to Harvest Watermelon:
Harvest watermelon 85 to 90 days after sowing seed, 35 to 45 days after flowers appear.
There are several ways to know a watermelon is ripe and ready to harvest:
- The fruit is the size you expect it to be at harvest; size varies by variety.
- The tendril closest to the fruit begins to wither, turn brown, and curl. If the tendril is green, the fruit is not ripe. If the tendril is dead, the fruit is ripe or overripe.
- The rind or skin loses it vibrant color and gloss and turns dull and there is little contrast between stripes on the skin.
- The bottom of the fruit where it touches the ground has a large white, cream, or yellow colored oval spot. The ground spot color at ripeness will vary with variety.
- When you thump the fruit you hear a low punk or thud sound. Unripe melons make a sharp ping sound when rapped.
Watermelons on the same plant typically ripen over a two week period. When the first melon is ripe, the others ripen shortly.
When the tendril closest to the fruit just begins to turn brown and wither, harvest will come in about a week. A week before harvest, decrease watering—water just enough to prevent the vine from wilting. Withholding water from a melon will cause the sugars in the fruit to concentrate. Too much water reduces sweetness.
In cool summers, the ripening process can be very slow, and the number of days to harvest will increase.
How to Harvest Watermelon:
Harvest watermelons by cutting the stem with a garden lopper or sharp knife close to the fruit. Handle the fruit gently to avoid bruising and breaking.
Cool watermelons immediately after harvest to remove field heat and prolong storage life. Place melons in a cool, shady spot or put them on ice.
How to Store Watermelon:
Storing watermelon. Watermelons can be stored uncut and unrefrigerated for about 10 days to 2 weeks. Place them in a very cool place to increase their storage time. If cut, watermelon will keep in the refrigerator for about 4 days wrapped tightly in plastic.
Watermelon will decay if stored below 50°F (10°C) for more than a few days.
Don’t store watermelons with apples or tomatoes which give off ethylene gas. The rinds of watermelons exposed to ethylene will thin and soften.
More tips: How to Grow Watermelon.