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When to Plant Celeriac in USDA Zone 3b

Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.

In Zone 3b, the average last spring frost is around May 10 and the first fall frost is around September 22, giving you a growing season of approximately 135 days.

Zone 3b Short season
135 days
Last Spring Frost May 10
135 growing days
First Fall Frost September 22

Celeriac Planting Timeline — Zone 3b

Where Is USDA Zone 3b?

The map below highlights the states that contain Zone 3b. Click any state to see the Celeriac planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Celeriac Planting Calendar — Zone 3b

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 10 May 10 – May 24
Direct Sow May 3 May 3 – May 24
Harvest August 23 Aug 23 – Sep 13
Fall Sowing June 30 Jun 30 – Jul 14

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June Fall Sowing
July Fall Sowing
August Harvest
September Harvest
October
November
December

Free Zone 3b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

High — keep soil consistently moist

Days to Maturity

100–120 days

Soil pH

6 – 7

Zone Temperature Range

-35°F to -30°F average annual minimum

Growing Season

135 days (Zone 3b average)

Planting Specifications

Planting Depth1 inches
Plant Spacing15 inches apart
Row Spacing24 inches between rows

Growing Tips for Celeriac in Zone 3b

Zone 3b has a short growing season (~135 days). Start Celeriac indoors early and use season-extension techniques like row covers and cold frames.

Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Level Up Your Garden

Saving Celeriac Seeds

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LED Grow Lights $25-60

Full-spectrum LED lights for starting seeds indoors when daylight is limited.

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Seedling Heat Mat $15-35

Warm soil for faster germination of heat-loving crops like tomatoes and peppers.

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Floating Row Covers $12-30

Protect plants from frost, wind, and pests while letting light and water through.

Related Plants

Frequently Asked Questions

When should I plant Celeriac in Zone 3b?

In Zone 3b, plan your Celeriac planting around the average last frost date of May 10. Start seeds indoors around March 29. Direct sow outdoors around May 3. Transplant seedlings around May 10.

Can Celeriac grow in Zone 3b?

Yes, Celeriac can grow well in Zone 3b, hardy in USDA zones 3a through 9b. Zone 3b has a growing season of approximately 135 days, which is sufficient for Celeriac (100-120 days to maturity).

When can I harvest Celeriac in Zone 3b?

In Zone 3b, expect to harvest Celeriac from August 23 – September 13. Celeriac takes 100-120 days from planting to harvest.

What is the last frost date for Zone 3b?

The average last spring frost in Zone 3b is around May 10, and the first fall frost is around September 22. This gives a growing season of approximately 135 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Celeriac?

Good companion plants for Celeriac include Leeks, Onion, Cabbage. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 3b, track your crops, and plan your garden season from seed to harvest.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.