Conover's Colossal Asparagus is a 19th-century heirloom that still dominates market gardens and home beds alike. Developed in the 1860s by New York produce merchant S.B. Conover, this variety was specifically bred for massive spears and exceptional yields, traits that made it legendary among farmers and that remain undiminished today. Hardy in zones 3 through 8, it produces buttery, tender spears year after year with the vigor and reliability that built its reputation. The heirloom genetics run deep, yet the performance is anything but nostalgic.
12
Full Sun
Moderate
3-8
?in H x ?in W
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High
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Conover's Colossal earned its name honestly: the spears grow thick and substantial, delivering the kind of abundance that justifies the space asparagus claims in a garden bed. Bred by a produce merchant who knew what markets demanded, it combines massive size with tender flesh and a buttery character that makes it shine whether grilled, roasted, or simply steamed. This is heirloom asparagus that performs like a modern hybrid, which is precisely why market farmers never stopped growing it and home gardeners keep returning to it.
Conover's Colossal is a culinary asparagus through and through. The substantial spears are thick enough to grill whole, developing a caramelized exterior while the interior stays tender. They roast beautifully, steam into tender submission, and excel in pasta dishes, soups, and preparations where size matters. Fresh, raw spears in salads showcase that buttery tenderness that makes this heirloom special.
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Plant asparagus crowns in early spring, as soon as soil can be worked, spacing them 12 inches apart. Dig planting holes deep enough to accommodate the crown without crowding, and mound soil gently over them as the plants emerge and grow through the season.
Begin harvesting in the second or third year after planting, once the bed is established. Cut or snap spears at or just below soil level when they reach 6 to 10 inches tall and before the tips begin to loosen and flower. Harvest regularly during the spring season to encourage continued production, and stop harvesting by early summer to allow the plant to build reserves for the following year.
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“S.B. Conover, a New York City produce merchant, created this variety in the 1860s by selectively breeding asparagus for the qualities that mattered most to commercial growers: extraordinarily large spears and prodigious yields. At a time when asparagus was becoming central to American market gardens, Conover's work produced a variety so successful that it became the standard by which other asparagus cultivars were measured. More than 150 years later, it remains beloved by both commercial and home gardeners, a testament to how careful selection for genuine agricultural merit creates varieties that endure across centuries.”