Blog

When to Plant Rutabaga in USDA Zone 4b

Rutabagas are a cross between turnips and cabbage, producing large yellow-fleshed roots with a sweet, mild flavor. They are excellent mashed, roasted, or in stews.

In Zone 4b, the average last spring frost is around May 1 and the first fall frost is around October 3, giving you a growing season of approximately 155 days.

Zone 4b Moderate season
155 days
Last Spring Frost May 1
155 growing days
First Fall Frost October 3

Rutabaga Planting Timeline — Zone 4b

Where Is USDA Zone 4b?

The map below highlights the states that contain Zone 4b. Click any state to see the Rutabaga planting schedule for that location.

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

Rutabaga Planting Calendar — Zone 4b

Activity When Date Range
Direct Sow April 24 Apr 24 – May 15
Fall Sowing July 11 Jul 11 – Jul 25
Harvest July 17 Jul 17 – Aug 21

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

Month-by-Month Timeline

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

Free Zone 4b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4b with start dates, transplant windows, and harvest times.

Get My Free Calendar →

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate — regular watering

Days to Maturity

80–100 days

Soil pH

6 – 7.5

Zone Temperature Range

-25°F to -20°F average annual minimum

Growing Season

155 days (Zone 4b average)

Planting Specifications

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

Growing Tips for Zone 4b

Direct sow in early summer for fall harvest. Thin seedlings to 6-8 inches apart. Flavor improves significantly after a few light frosts.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Saving Rutabaga Seeds

Recommended for Your Garden

💡
LED Grow Lights $25-60

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

🔥
Seedling Heat Mat $15-35

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

🪡
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 Rutabaga in Zone 4b?

In Zone 4b, plan your Rutabaga planting around the average last frost date of May 1. Direct sow outdoors around April 24.

Can Rutabaga grow in Zone 4b?

Yes, Rutabaga can grow well in Zone 4b, hardy in USDA zones 2a through 9b. Zone 4b has a growing season of approximately 155 days, which is sufficient for Rutabaga (80-100 days to maturity).

When can I harvest Rutabaga in Zone 4b?

In Zone 4b, expect to harvest Rutabaga from July 17 – August 21. Rutabaga takes 80-100 days from planting to harvest.

What is the last frost date for Zone 4b?

The average last spring frost in Zone 4b is around May 1, and the first fall frost is around October 3. This gives a growing season of approximately 155 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Rutabaga?

Good companion plants for Rutabaga include Peas, Onion, Carrots. 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 4b, track your crops, and plan your garden season from seed to harvest.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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.