What’s up with yellow or white patches on watermelons?

What you see:  A yellowish area on your watermelon. It may be slightly flatter than the rest of the melon. 
What it is: The ground spot! It’s where the watermelon rested on the soil while it was growing. 
Eat or toss: Eat! But, definitely clean that part of the melon thoroughly; it’s the dirtiest.

Why do watermelons have large yellow spots?

The yellow spot on a watermelon’s rind is where it rested on the ground while growing. That area didn’t get sunlight and thus didn’t green along with the rest of the fruit. It’s known as the “ground spot,” “field spot,” “belly spot,” or, most delightfully, “yellow belly.”

Is it OK to eat watermelon with a large yellow area?

It is absolutely OK to eat watermelon that has a large yellow area. In fact, that spot can give you a clue to how ripe the watermelon is. A creamy, yellow spot, something approaching the color of butter, is ideal for a standard melon. A spot that’s white or light green tells you that the watermelon didn’t fully ripen (but judge your watermelon accordingly; one with a lighter green exterior may have a lighter ground spot and still be perfectly ripe). Since watermelons don’t ripen after harvest, a melon with a green spot will never reach its full flavor potential. 

Make sure to wash watermelons thoroughly, especially the ground spot

When you’re preparing your watermelon, make sure to give it a good wash, paying special attention to the ground spot as it’s most likely to be carrying extra microbes from the soil.   

How to choose a watermelon

While many people believe a good thump is the best way to test a watermelon for ripeness, the folks at the National Watermelon Promotion Board discourage fruit aisle violence.  [Editor’s note: a run-by fruiting is also highly discouraged, especially for melons.]

“We don’t promote beating up the watermelon by thumping, patting, slapping, flicking or knocking,” the Board writes at Watermelon.org. 

Instead, they suggest looking for a good yellow spot. While experts seem to agree that eyeballing that spot is the best way to assess ripeness, here are some other strategies:

• Check the ends. According to the Purdue Extension, ripe watermelons often have faded tops and blunted ends. If the watermelon’s shape appears at all “pointy” it probably isn’t ripe yet. 
• Press test. Another way to evaluate ripeness, according to this handout from San Francisco State University, is to find the spot opposite the stem, which was the flower long ago. That area should yield slightly to a firm press. “If it feels as if you’re pressing into a table – then the melon is under-ripe,” the handout says.
• Scratch test. The Ohio State University extension advises that if you can easily scratch the rind and get to the green-white layer underneath, your melon should be ripe. Scratching an unripe melon will probably just leave a dark, depressed line. (But perhaps don’t tell the folks at the Watermelon Promotion Board, as we’re not sure how they feel about it.) 
• Calibrate your senses. And for you diehard thumpers, the watermelon enthusiasts at San Francisco State University suggest that instead of thumping, you contemplate a plastic bottle of water and a sack of flour to calibrate your melon-assessing senses. The plastic bottle, filled with water as it is, will have a feel that approximates a juicy watermelon. A mealy watermelon, with its lower water content, will feel more like the sack of flour when gently tapped: “dull, muted and dampened.”

Is it OK if a watermelon has scratches?

Don’t worry about small scratches on your melon, especially if they’re healed, Chad Crivelli writes in The Produce Nerd’s Grocery Guide: “A watermelon’s rind is thicker than most other melons. Because of this they can handle small scratches and rub marks.”

When is a watermelon ready to harvest?

If you’re picking a watermelon fresh from the field, the experts at the Postharvest Center at the University of California suggest looking for a wilted vine tendril near where the stem attaches.

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