Long-stemmed Leek
Autumn Giant Leek is a Western European heirloom that earned the Royal Horticultural Society's Award of Garden Merit for its exceptional reliability and culinary excellence. This midseason variety produces uniform stems with a thick white shank about 18 inches long, topped by medium green leaves that resist both bolting and bulbiness. Hardy from zones 6 through 11, it matures in 100 to 120 days and thrives as a cool-season crop celebrated for its fine flavor in traditional dishes like vichyssoise and potato leek pie.
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Moderate
6-11
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Perennial
Moderate
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Baker Creek describes this as an exemplary heirloom distinguished by its reliable, uniform growing ability and resistance to common leek problems like bolting and bulbiness. The thick white shank and consistent stem quality make it as dependable in the garden as it is on the table. Its RHS recognition reflects decades of careful observation by European growers who valued both productivity and taste.
This leek excels in slow-cooked, refined dishes where its fine flavor can shine. Vichyssoise, the classic French soup, relies on leeks like this for its characteristic smoothness and subtle sweetness. It also performs beautifully in potato and leek pie, gratins, and braises where the thick white shank becomes tender and mild with gentle cooking. The medium-length white portion makes it ideal for both rustic soups and elegant presentations.
Start seeds indoors in spring, maintaining soil temperatures between 50 and 70 degrees Fahrenheit for reliable germination. Sow seeds about 6 to 8 weeks before your planned transplant date in summer. This timing allows seedlings to establish strength before moving to the garden for an autumn harvest.
Transplant hardened-off seedlings outdoors in mid to late summer, positioning them in soil with a pH between 6.0 and 7.5. Space plants exactly 4 inches apart to accommodate the thick shank development this variety is known for. The midseason maturity means you're aiming for an autumn harvest, so time your transplanting to mature the leeks as temperatures cool.
Direct sow seeds in mid to late summer where you want them to grow, sowing at the appropriate depth and thinning seedlings to 4-inch spacing once they're large enough to handle.
Autumn Giant Leek matures in 100 to 120 days from transplanting, typically ready for harvest in fall. Harvest when the white shank reaches usable size, usually around 18 inches long, by gently loosening the soil around the base and pulling straight up. You can harvest individual leeks as needed or wait until most of the crop has reached full size. The frost-hardy nature means you can leave leeks in the ground well into autumn and early winter in zones 6 through 11, harvesting them as needed for fresh use.
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“Autumn Giant Leek carries the hallmark of Western European heirloom vegetables, developed and refined across generations in traditional gardening regions. The Royal Horticultural Society's formal recognition of its uniform stems and resistance to bolting speaks to its proven track record among both home and commercial growers in cool climates. This variety represents the kind of heirloom that survives because it works: gardeners kept replanting it, seed savers preserved it, and eventually it reached catalogs like Baker Creek, where it continues the European tradition of reliable, quality leek growing.”