We Asked a Farmer How to Pick Out a Ripe Watermelon—This Is What He Said

Juicy, ripe watermelon is one of the most delicious foods of summer. The fruit also offers myriad health benefits, thanks to its hydrating, antioxidant-boosting properties. But there are few moments more disappointing than cutting up that melon and finding that the flesh is mealy and bland. How can you tell whether the melon you choose will be a winner or a dud? 

The best way to ensure that the watermelon you’re bringing home from the grocery store or farmers’ market will taste sweet and flavorful is to choose a ripe one. To find out how to spot a perfectly ripe watermelon, we asked George Brittenburg, farmer and co-owner of Taproot Farm, a 200-acre certified organic fruit and vegetable farm in Berks County, Pennsylvania. 

Tips for Selecting a Ripe Watermelon

You’ve probably heard of several different ways to tell if the watermelons in your grocer’s bin are ripe, sweet and flavorful. Methods include thumping and listening for a hollow sound, feeling the weight of the fruit to see if it’s heavy for its size and looking for visual cues like yellow spots or “sugar bumps” on the skin. Unfortunately, most of those tricks don’t actually indicate whether a watermelon is ripe, Brittenburg said. In fact, there’s not much you can do to ascertain a watermelon’s ripeness after it leaves the field. 

“Watermelons should be harvested ripe, so the watermelons at the market should be ready to eat,” he explained. “In the field, we look for four signs. After the melons have sized up, the first sign is a puckering of the leaves. The second and most important sign is that the tendril that grows between the vine and the fruit will dry up completely.” At that point, the grower should be able to pull the fruit from the vine easily—another sure sign of ripeness. Watermelons that require more than a gentle tug to harvest should be left on the vine to continue ripening. 

The last sign that a watermelon is ready to pick is one that both you and the farmer who grew your fruit can use to gauge ripeness. “The bottom of the watermelon will often turn yellow,” Brittenburg says. “This may be a useful but not a definite indicator that the watermelon is ripe.” This can come in handy when you’re scoping out the tastiest-looking melon in your supermarket’s produce section. While it’s not a guarantee, a watermelon with a deep yellow “field spot”—the area of the skin that made contact with the ground—is more likely to be ripe and sweet than one with a spot that’s white or pale. 

According to Brittenburg, watermelons are unique among melons in these signs of ripeness. Other varieties, like cantaloupe, signal their ripeness when the skin of the fruit turns a deep tan color. When they’re at their peak, they’ll sometimes give off a pleasant aroma even before you’ve cut into them; however, he notes, a perfectly ripe cantaloupe may not smell sweet. 

Do Watermelons Continue to Ripen After They’re Picked? 

Watermelons differ from cantaloupes in another way when it comes to ripeness. After harvesting, cantaloupes will continue to ripen off the vine. But once a watermelon is picked, ripening stops—so no amount of time sitting on your counter or in your fridge will turn a disappointing, unripe watermelon into a sweet, juicy one. 

This means that the surest way to know that the watermelon you’re bringing to a summer barbecue or beach day is ripe is to purchase it from a trusted purveyor (though you can still look for that yellow spot for a little extra insurance). “The best watermelons are at the farmers’ markets or in a CSA share,” says Brittenburg. Because you’re purchasing directly from a farmer, there’s a higher level of quality control, not to mention a shorter supply chain from the field to your fridge.  

Aside from ripeness, another factor that could influence whether your watermelon tastes sweet rather than bland is whether it’s grown using organic or conventional farming methods. According to Brittenburg, “a watermelon grown in a healthy organic soil with all the proper nutrients will have a higher sugar content than a watermelon fertilized with chemical fertilizers.” 

Studies of the nutritional value of organic foods show that organic produce contains similar nutrient levels to conventionally grown—with the exception of phosphorus, which was 30 percent higher in organic fruits and vegetables. Phosphorus, an essential macronutrient for plants along with nitrogen and potassium, has been shown to contribute to sweeter, higher-quality fruit in studies of citrus. It’s possible that this benefit could also show up in organic watermelons.

How to Store Watermelon at Home

After you bring your watermelon home from the grocery store or farmers’ market, it’s important to store it properly. Since the fruit won’t continue ripening now that it’s been harvested, Brittenburg recommends keeping its time out of the fridge to a minimum. 

“Watermelons are tricky because they don’t store well under 40 degrees and also don’t store very long above 60 degrees,” he says. “I wouldn’t let a watermelon sit at room temperature for more time than I had to.” Instead, he recommends cutting up your watermelon as soon as possible, then stashing the pieces in an airtight container in your refrigerator (or serving it immediately). After that, fresh watermelon will keep in your fridge for about a week. You can also freeze watermelon for up to 8 months. Use it in recipes like smoothies, ice pops, mocktails or refreshing gazpacho.  

The Bottom Line 

The best way to tell if a watermelon is ripe is to buy it from a trustworthy purveyor. That’s because watermelons should be harvested only when the farmer notes signs of ripeness in the field. Once they reach your grocery store or farmers’ market, you can use one visual trick to increase the chances that your watermelon will be ripe: Look for one with a deep yellow field spot. Since watermelons won’t ripen off the vine, it’s best to cut and enjoy them as soon as possible, keeping cut fruit in a sealed container in the fridge for about a week or in the freezer for up to 8 months.