Kohlrabi

Heirloom Kohlrabi Seeds: The Quick-Growing "Alien" of the Garden

Kohlrabi (Brassica oleracea var. gongylodes) is perhaps the most visually striking and conversation-starting vegetable you can grow. At Firefly Farm & Mercantile, we curate heirloom kohlrabi seeds that are prized for their crisp, juicy texture and a flavor that sits perfectly between a sweet cabbage and a mild apple. Acclimated to the cool springs and autumns of the Driftless Region, our non-GMO varieties—including the classic "White Vienna" and the stunning "Purple Vienna"—are essential for gardeners who want a fast, reliable, and nutrient-dense harvest.

A Versatile Kitchen Staple: Stems, Leaves, and Crunch

Don't let its unusual appearance fool you; kohlrabi is incredibly easy to grow and highly versatile in the kitchen. We focus on vigorous heirloom varieties that can be harvested in as little as 45 days. The swollen, bulb-like stem is delicious when eaten raw like a turnip, roasted, or shredded into slaws. As a bonus, the leaves are also entirely edible and can be prepared just like kale or collards, making kohlrabi a high-yield choice for maximizing your northern garden space.

Quick Kohlrabi Growing Facts:

• Planting Window: Direct sow as soon as the soil can be worked in spring, and again in August for a fall harvest.
• Cold Hardiness: Very hardy; light frosts actually enhance the sweetness of the bulb and leaves.
• Hardiness Zones: Ideal for USDA Zones 3-8.
• Soil Preference: Requires rich, moist soil with a pH of 6.0 to 7.0 to prevent the bulbs from becoming tough.
• Expert Tip (The 3-Inch Rule): To avoid "woody" kohlrabi, harvest your bulbs when they reach the size of a tennis ball (about 2-3 inches in diameter). If you let them get much larger, the interior texture can become fibrous and lose its signature crunch.

Explore our selection of traditional white and purple heirloom kohlrabi seeds below. Every packet includes expert sowing instructions to help you grow a fast, high-yield, and unique harvest.