How to Pick a Ripe Watermelon

Learning how to pick a ripe watermelon is an important gardening skill. Picking a fresh melon in anticipation of its juicy sweetness, only to discover the melon isn’t nearly ripe, is a disappointing and frustrating experience. Doubly so, because unlike a cantaloupe, a watermelon won’t continue to ripen after it’s been picked.

And, unlike a cantaloupe, a ripe watermelon does not easily slip off the vine. So how can you tell when a watermelon is ripe for picking? Here are 9 features to look for.

Days to Maturity

The first clue to pay attention to is “days to maturity” on the seed packet. Not all melons on the same vine ripen at the same time, but “days to maturity” offers a good hint as to when to start watching for the melons to ripen. Of the two varieties I grow, Blacktail Mountain matures in approximately 75 days, Charleston Gray in 85 days.

Contrasting Stripes

Generally the watermelon’s skin will become dull and the contrast between the stripes will reduce as the melon ripens. This, of course, depends on the variety. Blacktail mountain, for instance, turns a real dark green with barely visible darker green stripes. A ripe Charleston Gray appears more veined than striped.

Hollow Sound

The standard method of determining whether or not a watermelon is ripe is to thump it with a knuckle or flick of a finger. A ripe watermelon makes a hollow, drum-like sound. I wouldn’t count on this method alone, as I’ve thumped plenty of hollow sounding melons that turned out not to be ripe.

Field Patch

The spot where the watermelon touches the ground while it grows is called the field patch, or sometimes field spot. If the patch is white, the melon isn’t ripe. A ripe melon has a yellow or cream-colored field patch. Different varieties of melon, and differing growing conditions, determine the field patch color. Generally, the warmer the weather, the darker the field patch.

Blossom End

When pressed with a thumb, the blossom end, opposite the stem end, of a ripe melon feels a little bit flexible. If it’s hard, the melon isn’t ripe yet. If it’s soft, the melon is probably past prime and starting to turn mealy.

Normal Size

Once you have experience growing a particular variety, you’ll have a general idea what the normal size of a ripe melon should be. Blacktail Mountain, for instance, is a small melon in the 6 to 10 pound range. Charleston Gray, on the other hand, is rather large at around 28 to 35 pounds.

Heavy for Size

Short of hauling a scale around the garden to weigh your melons, look for those that feel heavy for their size. The heavier a watermelon is compared to other melons of similar size on the same vine, the juicier and sweeter it should be.

Brown Tendril

If the tendril nearest the watermelon on the vine is green, the melon is still growing. When the tendril dries and turns brown, the melon should be ripe. On the other hand, in dry weather sometimes tendrils dry prematurely, so check for other signs before you decide if the melon is ready for picking.

Brown Vine

Sometimes — especially in hot, dry weather — the entire vine will wither and turn brown, whether or not the melons have ripened. Melons on a vine that is dead or dying will not ripen further, so you might as well take your chances and pick them. Even if they aren’t sweet enough for your taste, your chickens and goats will like them.

Then What?

Although a watermelon won’t ripen after it’s picked, in the sense that it won’t get any sweeter, it will continue to develop additional nutrients for up to two weeks when stored at room temperature. A watermelon stored in the fridge, however, will begin deteriorating in flavor and texture.

A fresh watermelon will keep well for several weeks at room temperature. If you like your watermelon ice cold, chill it just before serving it. Then refrigerate any left-overs after the melon has been cut into. On the other hand, if you pick a really ripe, sweet, juicy watermelon, you’re unlikely to have much left over after everyone digs in.