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When to Plant Rutabaga in Fairbanks North Star Borough, AK

Fairbanks North Star Borough, Alaska Zone 3b May

Your May gardening checklist

Welcome to May in Zone 3b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 15
Avg. first frost September 8
Soil temp (4") 42°F
Watering Critical
Pest pressure Low
Daylight 18.2 hrs
  1. Plant rutabaga from seed, right in the garden

    Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.

A few tasks this May that'll pay off in June
  • Fall sowing: rutabaga

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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.

Fairbanks North Star Borough, Alaska is in USDA Zone 3b. The average last spring frost is May 15 and the first fall frost is September 8, giving you a growing season of approximately 116 days.

At an elevation of 2,540 feet, Fairbanks North Star Borough receives approximately 29.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 69°F, so choose short-season varieties of Rutabaga to ensure they mature before fall.

Fairbanks North Star Borough, AK (Zone 3b) Short season
116 days
Last Spring Frost May 15
116 growing days
First Fall Frost September 8

Fairbanks North Star Borough Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 11 🍅 Harvest: Aug 3 – Sep 7
Recommended (50%) ✗ May not fit
Transplant: May 15 🍅 Harvest: Aug 7 – Sep 11
Safe Start (90%) ✗ May not fit
Transplant: May 30 🍅 Harvest: Aug 22 – Sep 26

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 Fairbanks North Star Borough

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

Soil pH

Your soil pH (5.2–6.4) is more acidic than Rutabaga prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Fairbanks North Star Borough is excellent for Rutabaga — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Rutabaga.

Organic Matter

Organic matter is excellent (6.7%) — 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.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.1″/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 1.6" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1" 0" ❄️ Dormant
Apr 1" 0" ❄️ Dormant
May 3" 1.2" 1.8" 🚿 Regular watering
Jun 3" 2.4" 0.6" 💧 Light watering
Jul 3" 3.3" 0" ✅ Rainfall sufficient
Aug 3" 4.1" 0" ✅ Rainfall sufficient
Sep 3" 5.3" 0" ✅ Rainfall sufficient
Oct 3.8" 0" ❄️ Dormant
Nov 2.2" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Fairbanks North Star Borough). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~158 GDD — county provides 203 GDD Good fit

Rutabaga Planting Timeline — Fairbanks North Star Borough, AK

Rutabaga Planting Calendar

Activity When Date Range
Direct Sow May 8 May 8 – May 29
Harvest July 31 Jul 31 – Sep 4
Fall Sowing June 16 Jun 16 – Jun 30

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

80–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 3b

📆 Growing Season

116 days in Fairbanks North Star Borough

Growing Tips for Rutabaga in Fairbanks North Star Borough

Direct sow Rutabaga outdoors after May 15 in Fairbanks North Star Borough 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 Fairbanks North Star Borough, AK?

Fairbanks North Star Borough is in Zone 3b with an average last frost of May 15. Plan your Rutabaga planting based on this frost date — see the calendar above for exact timing.

What planting zone is Fairbanks North Star Borough, AK?

Fairbanks North Star Borough, Alaska is in USDA Hardiness Zone 3b. The average last spring frost is May 15 and first fall frost is September 8.

🌱

Your Fairbanks North Star Borough Garden Planner — Free

A 24-page printable planner built for Fairbanks North Star Borough (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Fairbanks North Star Borough, AK. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.