Kohlrabi illustration

Growing Kohlrabi in Zone 3a

Zone 3a has harsh winters and a short growing season. Start Kohlrabi early indoors to maximize your harvest window. Last frost: May 22. First frost: Sep 12.

Planting Calendar

Indoor
Outdoor
Harvest
Apr 10Sep 12

Season: May 22 – Sep 12 (113 days) · Succession: plant every 3 weeks (up to 2x)

Zone3a
Last FrostMay 22
First FrostSep 12
Season Length113 days
Days to Harvest55
SunFull Sun
Frost ToleranceModerate
Spacing6/sqft

When to Plant Kohlrabi in Zone 3a

Start Seeds Indoors: Apr 10

Start Kohlrabi seeds indoors around Apr 10 (6 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 5–10 days.

Transplant Outdoors: May 1

Transplant Kohlrabi seedlings outdoors after May 1. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.

Harvest: Jun 10

First harvest approximately Jun 10 (~40 days from transplant). Continue harvesting until first frost (Sep 12).

Fall Planting: Jul 18

For a fall harvest, plant Kohlrabi around Jul 18 (8 weeks before first frost).

Frequently Asked Questions

When should I plant Kohlrabi in Zone 3a?

Start Kohlrabi seeds indoors around Apr 10. Transplant outdoors after May 1. Expect first harvest around Jun 10.

What is the last frost date for Zone 3a?

The average last spring frost date for Zone 3a is May 22. The first fall frost averages Sep 12, giving a 113-day growing season.

Can I grow Kohlrabi in Zone 3a?

Yes. Kohlrabi needs 55 days to harvest. Zone 3a has a 113-day growing season, which is sufficient. You can plant up to 2 successions.

What is the best month to plant Kohlrabi in Zone 3a?

The best time to start Kohlrabi in Zone 3a is Apr. Begin seeds indoors around Apr 10, then transplant outdoors after the last frost date of May 22.

How long does Kohlrabi take to harvest?

Kohlrabi takes approximately 55 days from planting to harvest. In Zone 3a, expect your first harvest around Jun 10.

Plan Your Kohlrabi Garden

Track Kohlrabi from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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