Watermelons can be thumped, turn yellow and grow pigtails when ripe

Crimson Sweet watermoelon and

Persian melon at the orchard

Q. I have several watermelons on the vine. How am I able to tell when they're ripe? Can you "store them" on the vine? I had one split open by itself and it was mostly white inside. After 50 years I still have trouble buying a commercial watermelon, whenever I think I have found the right characteristics I'm proved wrong.

A. Watermelons do not continue to ripen after they are picked so what is important to pick them at the right time. This is not true of many of the other melons such as muskmelon. Once picked from your garden, you can store many melons at 50-60° F for a couple of weeks. This may not be true of store bought melons.

Basically there are three methods used for determining if a melon is ripe or not. This includes the color of the melon touching the ground, thumping them and drying of the tendrils on the vine close to the fruit. Personally I just use two; the color of the melon touching the ground and thumping. Tendrils are tiny extensions of the vine close to the fruit that look a little bit like a corkscrew or pig’s tale.

The bottom of a watermelon should be turning lemon yellow instead of pale yellow or white on many watermelons. Thumping watermelons can be tricky unless you can learn what the thump is supposed to sound like. It should have a dull, resonating sound that vibrates through the entire melon. It is important to pickup a melon to thump it, not leave it on the ground when thumping. If you’re in a store, pick it up to thump it.