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Black diamond watermelons are ready to pick when the tendril closest to the fruit turns brown and dry, the ground spot becomes a creamy yellow, and the rind produces a deep hollow sound when thumped.
But nailing down the exact moment these watermelons are ready to pick takes a bit more than a simple glance, so let’s dig into the details.
You’ve probably heard the old gardener’s tricks, but black diamond watermelons have a few unique quirks that make timing everything for that perfect, sugary bite.
In this post, we’ll cover the signs that tell you when black diamond watermelons are ready to pick, the common pitfalls to avoid, and how to harvest them like a pro.
Let’s get into it so you can enjoy the sweetest melon of the season.
Signs Black Diamond Watermelons Are Ready To Pick
Black diamond watermelons are ready to pick when several signals align, and here’s what you need to watch for.
1. The Curly Tendril Turns Brown
The most reliable sign that black diamond watermelons are ready to pick is the little curly tendril near the stem.
This tendril looks like a small, coiled spring, and it starts out green and flexible.
When black diamond watermelons are ready to pick, that tendril will turn brown, dry out, and become brittle.
If the tendril is still green and pliable, your melon isn’t ready yet, so give it a few more days.
Once that tendril is fully brown and crispy, you can be confident black diamond watermelons are ready to pick.
2. The Ground Spot Turns Creamy Yellow
Another huge clue that black diamond watermelons are ready to pick is the color of the ground spot.
The ground spot is the pale area on the underside of the melon where it rests on the soil.
When the watermelon is immature, this spot is white or pale green.
As black diamond watermelons become ready to pick, that spot transitions to a rich, creamy yellow or even a buttery orange.
The deeper and yellower the ground spot, the riper the melon, so flip it gently and take a peek.
3. The Rind’s Dull Appearance and Toughness
Black diamond watermelons are ready to pick when the rind changes from shiny to dull.
A young, unripe melon has a glossy, almost reflective surface, while a ripe one looks matte and muted.
You can also press your thumbnail into the rind to test it.
If black diamond watermelons are ready to pick, the rind will be tough and resist your thumbnail’s pressure.
If the rind punctures easily, the melon is still immature, so wait a bit longer.
4. The Hollow Sound Test
Give your black diamond watermelon a good thump with your knuckles and listen carefully.
When black diamond watermelons are ready to pick, they produce a deep, hollow, resonant sound, almost like a drum.
An underripe melon will sound more like a high-pitched, metallic ping.
An overripe melon might sound dull and thuddy, so you want that sweet spot of hollowness.
This test takes a little practice, but it’s a fun and handy way to double-check your other signs.
5. Counting Days from Flowering
Black diamond watermelons are ready to pick roughly 85 to 95 days after planting, or about 35 to 45 days after the female flowers appear.
Mark your calendar when you see those small, fuzzy female flowers start to swell into tiny melons.
From that pollination date, start checking your melons daily around day 35.
By day 45, most black diamond watermelons are ready to pick, assuming weather conditions have been favorable.
How To Pick Black Diamond Watermelons Without Damaging Them
Once you’ve confirmed black diamond watermelons are ready to pick, the next step is harvesting them correctly.
1. Cut, Don’t Pull
Never yank a watermelon off the vine because you might damage the fruit or the plant.
Instead, use a sharp knife or pruning shears to cut the stem about two inches above the melon.
Leaving a bit of stem attached helps the watermelon stay fresh longer after you’ve picked it.
2. Handle With Care
Black diamond watermelons are heavy, sometimes reaching 40 to 50 pounds, so be careful when lifting.
Support the melon from underneath with both hands to avoid bruising the rind.
Even though the rind is tough, a hard drop can cause internal cracking that ruins the flesh.
3. Store Them Properly After Picking
After black diamond watermelons are ready to pick and you’ve cut them free, move them to a cool, shaded spot.
At room temperature, they’ll stay good for about a week or two.
If you want to keep them longer, pop them in the fridge, where they can last for up to three weeks.
Just remember that refrigeration can mute the flavor a bit, so let the melon sit at room temperature for an hour before slicing for the best taste.
Common Mistakes When Checking If Black Diamond Watermelons Are Ready To Pick
Even experienced gardeners get tripped up, so here’s what to avoid.
1. Relying on Just One Sign
Don’t judge ripeness based on a single indicator, like just the sound or just the tendril.
Black diamond watermelons are ready to pick when multiple signs align together.
Check the tendril, the ground spot, the rind, and the sound, and if at least three out of four match, you’re good to go.
2. Picking Too Early Out of Excitement
It’s tempting to harvest as soon as the melon looks big, but size alone doesn’t mean it’s ripe.
Black diamond watermelons are ready to pick only when they’ve had enough time to develop sugars.
If you pick too early, you’ll get a crunchy, bland melon with pale, tasteless flesh.
Patience truly pays off with this variety.
3. Ignoring Weather Effects
Hot, sunny weather speeds up ripening, while cool, cloudy spells slow it down.
So your day-count estimate might be off by a week or more depending on your local climate.
Always combine day counting with physical signs to know when black diamond watermelons are ready to pick.
So, When Are Black Diamond Watermelons Ready To Pick?
Black diamond watermelons are ready to pick when the tendril browns, the ground spot yellows, the rind dulls, and the melon sounds hollow.
You don’t need to be a master gardener to figure this out, just a keen observer.
Check all the signs together, count your days from flowering, and you’ll have perfectly ripe, juicy black diamond watermelons every single time.
Happy harvesting, and enjoy that sweet, refreshing payoff!