Kossak

Kohlrabi

Zone 3a Save Garden

🌱 75d to harvest Rosette

Tender, sweet-snap Kossak kohlrabi forms a smooth, globe-like bulb that rises boldly above the soil—its skin a clean, luminous pa…

Crop Dates

Milestone	Date
Start Indoors	Apr 17th
Last Frost	May 15th
Transplant / Sow Outdoors	May 15th
Harvest Begins	Jul 29th
Harvest Ends	Sep 1st

Crop Details

Trait	Value
Days to Maturity	75
Sun Requirements	Full Sun
Growth Habit	Rosette
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	45
Min Soil Temp (°F)	40
Min Night Temp (°F)	30
Harden Off (days)	6

Recommended Companions

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Frequently Asked Questions

What pest or disease commonly affects kohlrabi (Brassica oleracea var. gongylodes), and how can I manage it at home?

Kohlrabi is commonly hit by cabbage worms (imported cabbageworm/diamondback moth larvae) and aphids; look for holes in leaves and sticky leaves or clusters of insects. Hand-pick larvae early and spray with Bacillus thuringiensis (Bt) labeled for caterpillars on Brassicas, and blast aphids off with a firm water spray before they multiply. If you see black-brown spots and leaf yellowing, remove affected leaves promptly and avoid wetting foliage to reduce spread of fungal leaf diseases.

How often should I water kohlrabi during the main growing phase?

During the 6–8 weeks when the bulb forms, keep soil consistently moist but not waterlogged—aim for about 1 inch (2.5 cm) of water per week, adjusting for heat and container use. Let the top 1 inch of soil dry slightly between waterings to prevent rot while maintaining steady growth; irregular watering can cause woody, pithy bulbs. Mulch helps hold moisture so the swelling globe forms smoothly.

How do I tell when kohlrabi is ready to harvest (75 days)?

Harvest when the globe (swollen stem) is firm and roughly 2–4 inches (5–10 cm) across, typically around 75 days from sowing depending on conditions. If it looks much larger and starts to feel hard or fibrous, it will likely be tough and more pungent. Use a knife to cut the bulb at the base, and harvest promptly rather than letting it sit.

Tender, sweet-snap Kossak kohlrabi forms a smooth, globe-like bulb that rises boldly above the soil—its skin a clean, luminous pale green with a faint blush where light kisses it. The flesh is crisp and juicy, with a fine, succulent texture that stays pleasantly mild even as it nears maturity. Grow Kossak for fresh salads, quick roasting, and bright slaws, or for creamy sauces that showcase its gentle, cabbage-sweet character.

Sowing Tips

Transplant Conditions

Wait until soil reaches 40°F and nights stay above 30°F before moving outdoors. Harden off for 6 days first.

Expert Note

For best texture, keep consistent moisture and harvest kohlrabi when bulbs are tennis-ball to fist-size—overgrown bulbs can become fibrous even if they stay flavorful.