Icebox Watermelon
Blacktail Mountain is one of the earliest watermelons available, developed by Glenn Drowns at the Sand Hill Preservation Center in Iowa and beloved by gardeners across the U.S. for its remarkable ability to thrive in both northern gardens and hot, dry climates. The dark-ringed fruits weigh 8 to 12 pounds each and contain deeply sweet, red flesh that tastes as good as any melon you'll grow. Maturing in just 70 to 80 days from seed, it reaches full productivity in hardiness zones 3 through 11, making it genuinely accessible to most American gardeners. This heirloom has earned its reputation through reliable performance and exceptional flavor, delivering the full promise of summer in a compact, manageable package.
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Blacktail Mountain germinates quickly, sending up seedlings in just 5 to 10 days, and reaches harvest-ready fruit faster than most other watermelon varieties. Glenn Drowns' careful development created a melon that handles both the cool nights of northern gardens and the heat and drought stress of southern summers with equal grace. The combination of early maturity, genuine cold tolerance, sweet red flesh, and moderate fruit size means you actually get to eat your watermelons before the season ends, something northern gardeners especially appreciate.
Blacktail Mountain watermelons are eaten fresh, either chilled and sliced as a summer dessert or added to fruit salads. The moderate 8 to 12-pound size makes these melons practical for families and small households, eliminating the waste that can occur with larger varieties. Some gardeners save seeds from mature fruits, keeping this heirloom in circulation through informal seed networks.
Direct sow seeds outdoors once soil temperature reaches 70 to 85 degrees Fahrenheit, which typically occurs in late spring or early summer depending on your zone. Seeds sprout within 5 to 10 days when soil is warm enough. Plant at the proper depth (see seedDepth) and thin seedlings once they've developed their first true leaves.
Blacktail Mountain watermelons are ready to pick when the tendril closest to the fruit has dried and turned brown, or when the spot where the fruit rests on the ground has turned from pale to golden yellow. Harvest in the cool early morning hours when temperatures are lowest, then chill the fruit quickly. Remember that watermelons do not continue ripening once picked from the vine, so confirm full maturity before harvesting. Expect harvest 70 to 80 days after planting.
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“This variety owes its existence to Glenn Drowns, owner of the Sand Hill Preservation Center in Iowa, who developed Blacktail Mountain specifically to extend watermelon growing into regions where the traditional long-season varieties couldn't complete their cycle. Rather than adapt a southern melon north, Drowns bred for speed without sacrificing quality, creating an heirloom that has become a favorite among seed savers and gardeners who value both heritage and practicality. The variety's success across diverse climates and its preservation through seed-saving networks demonstrate how thoughtful crop development by dedicated individuals creates ripples through gardening communities for generations.”