How to Tell If a Watermelon Is Ripe
These eight easy tricks will help you determine if a watermelon is ready to buy or to harvest.
Growing watermelons is nothing short of magic. Tuck a small seed into the ground, and it grows into a vine that produces watermelons. Biting into a luscious, juicy slice of watermelon you grew yourself is one of gardening's sweetest rewards.
Watermelons aren't hard to grow. The toughest part of the process is knowing how to tell if a watermelon is ripe. Once you pick it, the melon doesn't ripen further, so you need to get it right. Pick it too soon, and it's inedible. Pick too late, and the flesh is watery.
The thing is, even with all of the technological advances at our fingertips, there's still no one foolproof way to pick the perfect watermelon. It's more of an art with a Sherlock Holmes vibe as you gather clues and draw a conclusion. To get started as a watermelon whisperer, try these eight tips to tell if a watermelon is ripe and ready for picking.
Ways to Tell if Your Watermelon Is Ripe
1: Check for a Brown Tendril
A watermelon vine has curly tendrils on it. Find the one that's closest to a ripening watermelon fruit. That tendril gives excellent clues for when a watermelon is ripe. When the melon is small and developing, the tendril is green and pliable. As the watermelon ripens, the tendril starts to lose its green color, becoming brown. When the watermelon is fully ripe, the tendril is brown and dry. A fully ripe watermelon with brown tendril will keep on the vine up to two weeks as long as no heavy rainfall occurs, which causes ripe melons to split open (like tomatoes).
The exception to the brown tendril rule is 'Sugar Baby,' an icebox-type watermelon. When the tendril turns brown and dries, you need to wait another seven to 10 days before picking. Use an industrial marker (found in the tool section at home centers) to mark the melon with the date the tendril is brown and dry. Then it's easy to track another week to 10 days.
2: It's All About Timing
Another clue that tells if a watermelon is ripe is how long it's been growing. The seed packet spells out how many days it takes for a watermelon to ripen from the date of planting. It's typically a range like 80 to 120 days. If you're growing watermelon from seedlings your bought, just note when flowers open. It typically takes about five calendar weeks for a watermelon to go from flower to ripe fruit.
3: Look at Rind Appearance
Julie Martens Forney
When a watermelon is immature, the rind has a sheen to it. As a watermelon ripens, the sheen disappears and the rind becomes dull. Experienced watermelon farmers also say that the surface changes from feeling smooth to having an almost wavy or rough feel to it. If your watermelon variety has stripes on the fruit, you'll notice a strong contrast between the stripe and background colors when the melon is ripe.
4: Observe the Ground Spot
A spot develops where a ripening watermelon rests against the ground. It starts white, then gradually changes color as the watermelon ripens. It usually turns bright yellow, although some varieties may look more beige. This watermelon (above) has a yellow ground spot, but the melon isn't fully ripe because you can still see green speckles in the yellow field. 'Sugar Baby' and a few other dark-skinned melons develop a bright ground spot early in their development, long before the melon is ripe. This is why you have to use several clues to make your final determination if a watermelon is ready for picking.
5: Test the Sound
A fully ripe watermelon has a distinctive sound when you thump it. To thump a watermelon, brace the tip of your middle finger against your thumb and flick it against the melon. (It's the same motion you probably used to thwap a sibling or friend as a child.) This sets up a sort of seismic wave inside the melon and produces a sound. A dull or hollow ringing sound (a plunk) reveals a ripe melon, while a high-pitched, metallic plinking or pinging sound means you should let that melon ripen some more. Train your ear by testing unripe melons to learn what they sound like.
6: What's the Weight?
A ripe watermelon should feel heavy for its size. Most seed packets or seedling pot stakes mention how large watermelons should be when ripe. Use this information as a guide, knowing that sometimes, due to growing conditions, melons may mature larger or smaller.
7: Is It Easy To Pick?
When a watermelon is fully ripe, it's easy to pick from the vine. It won't slip off like a cantaloupe, but you won't have to pull with all your strength to get it free. A gentle tug and it should come free.
8: Try an App
Several apps exist that measure a watermelon's ripeness: iWatermelon Deluxe for iPhone and iPad; Melony watermelon ripeness app for Android. To operate, place your device on the watermelon and tap it three times. The app uses sound analysis algorithms to determine if the melon is ripe.