🍉 Blacktail Mountain Watermelon

What it looks like

Why this variety

Blacktail Mountain was bred in Idaho for places where summer is a rumor: it ripens in just 70 to 75 days, producing 8 to 12-pound, dark green melons with sweet red flesh. It is the earliest reliable watermelon in the catalog, and it earned its reputation by fruiting where other melons merely made vines and excuses.

In Florida, earliness plays a different role: Blacktail Mountain is your first melon of the season and your insurance policy. Plant it in the earliest spring window and you are eating watermelon while the big picnic varieties are still deciding whether to set fruit — and if a late-summer disease wave hits, the early variety has already paid you. The fruit is smaller than a picnic melon, but the flavor is not a consolation prize.

If you are new to choosing between cultivars, the Varieties Matter guide explains why the name after the plant matters as much as the plant itself.

How to grow

Watermelons want heat, sun, and room to be dramatic. Start seed indoors 2 to 3 weeks before your last frost date, or direct-sow once the soil is reliably above 70°F — cold soil rots seed before it ever sprouts, and a watermelon seedling chilled early never really forgives you. In Florida, spring planting runs roughly February to March in the north, January to March further south, with a second fall window in August and September. Give each plant a hill or a wide row and space to run: vines routinely stretch 6 to 10 feet, and crowding them is how mildew parties start.

Give it the same warm soil and full sun as any melon, and do not let its northern reputation fool you into planting it in cool soil — early varieties still want heat, they just need less of it. In Florida, treat Blacktail Mountain as a spring and fall variety, not a midsummer one, and it will reward you twice a year.

Bees do the pollination, so do not spray insecticide on open flowers in the morning when bees are working. A female flower wears a tiny melon behind the petals; if it yellows and drops, it was not pollinated, and the usual culprit is too few pollinators, not your soil. Black plastic or landscape fabric warms the soil and holds moisture in spring plantings, but in a Florida summer it can cook roots — straw mulch is the safer summer bet.

Water & feeding

Water deeply and consistently, especially while fruit is sizing — a melon is about 92 percent water, and it is not shy about where that water comes from. An inch or two a week, delivered at the soil line, keeps growth steady. Ease off slightly as fruit ripens; a flood right before harvest dilutes sugars and can split rinds.

Feed moderately at planting with castings worked into the hill, then side-dress once vines start running and again at first fruit set. Too much nitrogen late in the season grows leaves instead of melons and delays ripening, which is the opposite of the deal.

Common problems

• Fusarium wilt — vines yellow and collapse, often on one side first. Rotate beds, choose resistant varieties where available, and never plant melons in the same spot year after year.
• Downy and powdery mildew — humid Florida air is their home turf. Space for airflow, water at the soil line, and remove badly infected leaves promptly.
• Anthracnose and gummy stem blight — leaf spots and stem cankers in wet weather. Rotate, mulch to stop soil splash, and buy clean seed.
• Pickleworm and rindworm — caterpillars that bore into fruit. Scout under leaves, use row cover until flowering (then remove it so bees can pollinate), and pick damaged fruit early.
• Aphids and cucumber beetles — aphids spread viruses and beetles chew seedlings. Row cover early, strong water blasts for aphids, and hand-picking for beetles on small plantings.

Harvest

Pick when the nearest tendril dries, the ground spot yellows, and the thump turns hollow and dull. Blacktail Mountain ripens fast once it starts, so check every couple of days at the end — an overripe melon goes mealy, and mealy is a tragedy with no remedy.

Store whole melons in a cool spot for a week or two; cut melon goes in the fridge and gets eaten fast, because it does not improve with age. Save seed only from fully ripe, open-pollinated fruit, and keep varieties separated if you want the seed to stay true — watermelons cross with enthusiasm.

Saving seeds

Blacktail Mountain is an open-pollinated variety, so it comes true from seed — save seed from your best fruit, and keep it away from other watermelons to avoid crossing. The full method is in the Saving seeds section of the Watermelon guide.