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When to Plant Rutabaga in Washington County, MN

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.

Washington County, Minnesota is in USDA Zone 4a. The average last spring frost is April 23 and the first fall frost is October 9, giving you a growing season of approximately 169 days.

At an elevation of 832 feet, Washington County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Rutabaga during the growing season.

Washington County, MN (Zone 4a) Moderate season
169 days
Last Spring Frost April 23
169 growing days
First Fall Frost October 9

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (51 days to spare)
Transplant: Apr 17 🍅 Harvest: Jul 10 – Aug 14
Recommended (50%) ✓ Fits season (50 days to spare)
Transplant: Apr 23 🍅 Harvest: Jul 16 – Aug 20
Safe Start (90%) ✓ Fits season (47 days to spare)
Transplant: May 13 🍅 Harvest: Aug 5 – Sep 9

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Washington County

How your county's soil matches Rutabaga's growing requirements.

Soil pH

Your soil pH (5.8โ€“6.9) overlaps with Rutabaga's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Washington County is excellent for Rutabaga โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.7%) โ€” Rutabaga will thrive.

How to Plant Rutabaga

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Rutabaga

2
successive plantings in your 169-day season

Sow every 9.1 weeks. Last sowing by Jul 01 to harvest before frost.

For a dedicated fall crop, sow by Jul 17.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Rutabaga

Rutabaga needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Rutabaga Needs Rainfall You Supplement Action
Jan โ€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 1.6" 0" โ„๏ธ Dormant
Mar โ€” 2.4" 0" โ„๏ธ Dormant
Apr 3" 3" 0" โœ… Rainfall sufficient
May 3" 3.4" 0" โœ… Rainfall sufficient
Jun 3" 4.1" 0" โœ… Rainfall sufficient
Jul 3" 3.1" 0" โœ… Rainfall sufficient
Aug 3" 3.3" 0" โœ… Rainfall sufficient
Sep 3" 2.4" 0.6" ๐Ÿ’ง Light watering
Oct 3" 2.4" 0.6" ๐Ÿ’ง Light watering
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 1.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Washington County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Rutabaga Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Rutabaga needs ~1,238 GDD — county provides 2,323 GDD Excellent fit

Rutabaga Planting Timeline โ€” Washington County, MN

Rutabaga Planting Calendar

Activity When Date Range
Direct Sow April 16 Apr 16 โ€“ May 7
Harvest July 9 Jul 9 โ€“ Aug 13
Fall Sowing July 17 Jul 17 โ€“ Jul 31

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

80โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

169 days in Washington County

Growing Tips for Rutabaga in Washington County

Direct sow Rutabaga outdoors after April 23 in Washington County when soil has warmed and frost danger has passed.

Common pests for Rutabaga in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Rutabaga in Washington County, MN?

Washington County is in Zone 4a with an average last frost of April 23. Plan your Rutabaga planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, MN?

Washington County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is April 23 and first fall frost is October 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washington County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

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. Frost dates are based on 50% probability averages for Washington County, MN. Local conditions may vary. Last updated: April 2026.