Watermelon Beefsteak is a heirloom tomato with deep roots in American seed-saving history, originating over 100 years ago with legendary seedsman George Gleckler. This indeterminate slicing tomato produces extremely large, nearly square fruits measuring 6 by 4-5 inches, with flesh that transitions from dark green to bright cherry red as it ripens. The flavor is famously melt-in-your-mouth tender and sweet with a mild character that makes it a revelation on the plate. Ready to harvest in 70-79 days from transplant, it thrives in full sun and reaches 18-24 inches tall, adapting well to garden plots, raised beds, and greenhouses alike.
18
Full Sun
Moderate
2-11
24in H x ?in W
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High
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George Gleckler preserved this variety over a century ago, and it remains a testament to what careful seed saving can achieve. The fruits are strikingly massive and almost square in shape, with a radiant pink-red color and that distinctive dark green interior that gives the variety its watermelon name. What truly sets it apart is the texture: the flesh is so tender it practically melts on the tongue, sweet and mild enough that even tomato skeptics tend to come around.
Watermelon Beefsteak excels as a slicing tomato, its large, sturdy fruits cutting cleanly into thick slices for fresh summer sandwiches and salads where its mild sweetness shines without overpowering other ingredients. The substantial size makes it practical for canning whole or in halves, and the tender flesh breaks down beautifully for fresh sauces or gazpacho. Its sweet, mild character also makes it approachable for anyone who finds typical tomato acidity off-putting.
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Start seeds indoors 6-8 weeks before your last frost date. Sow seeds 1/4 inch deep in warm soil (70-80°F) and maintain consistent moisture. Seedlings should emerge in 5-10 days. Once true leaves appear, thin or transplant into individual containers and grow under bright light.
Harden off seedlings over 7-10 days by gradually exposing them to outdoor conditions. Transplant outdoors only after soil temperature reaches at least 60°F and all frost danger has passed. Dig a hole slightly deeper than the root ball; burying the stem encourages a stronger root system. Space plants 18 inches apart with rows 36 inches apart.
Watermelon Beefsteak reaches harvest readiness in 70-79 days from transplant. Pick fruits when they show a full, radiant pink-red color and yield slightly to gentle hand pressure. The flesh transitions from dark green to bright cherry red as it ripens, and fully ripe fruits detach cleanly from the vine with a gentle twist. For peak flavor and sweetness, harvest in the morning after the dew dries but before full afternoon heat.
As an indeterminate type, Watermelon Beefsteak grows continuously and benefits from selective pruning to manage vigor and improve fruiting. Pinch out the growing tip 4-6 weeks before your first expected frost to halt new flower production and allow existing fruits to finish ripening. During the season, remove lower leaves once the plant is 12-18 inches tall to improve air circulation and reduce disease pressure. Prune off suckers (shoots growing between the main stem and branches) to direct energy toward fruit production, though some gardeners prefer to leave a few to increase overall yield.
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“Watermelon Beefsteak carries the legacy of George Gleckler, one of America's most respected seedsmen, who developed and preserved this variety over 100 years ago. Gleckler's meticulous work in seed selection created a tomato that has endured through generations of home gardeners who recognized something special in its size, shape, and flavor. The variety represents the era when American seed companies were actively breeding distinctive regional types rather than standardizing everything into a handful of commercial lines. Its survival to today is the direct result of gardeners who valued it enough to save seeds year after year, keeping Gleckler's original work alive in their own gardens.”