When to Plant Kohlrabi in Southeast Fairbanks, AK
Top priorities for Southeast Fairbanks, Alaska gardeners in May
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Seed kohlrabi outdoors
These tolerate cool soil, so you're not gambling by sowing now.
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Plant your fall garden: kohlrabi
A row cover ready in the garage extends your harvest by weeks once the nights turn cold.
Looking ahead to June
- Transplants going out: kohlrabi
Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.
Southeast Fairbanks, Alaska is in USDA Zone 2a. The average last spring frost is June 6 and the first fall frost is August 17, giving you a growing season of approximately 72 days.
At an elevation of 1,414 feet, Southeast Fairbanks receives approximately 39.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 62°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall.
Southeast Fairbanks Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.6
Drainage
Well Drained
Plant Planting Risk Windows
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 Southeast Fairbanks
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (4.9–6.6) is more acidic than Kohlrabi prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Southeast Fairbanks is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Kohlrabi.
Organic Matter
Organic matter is excellent (6.3%) — Kohlrabi will thrive.
How to Plant Kohlrabi
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Kohlrabi
Kohlrabi needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Kohlrabi Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | — | 1.8" | 0" | ❄️ Dormant |
| Jun | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Sep | — | 6.6" | 0" | ❄️ Dormant |
| Oct | — | 4.5" | 0" | ❄️ Dormant |
| Nov | — | 3.3" | 0" | ❄️ Dormant |
| Dec | — | 2.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Aug in Southeast Fairbanks). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kohlrabi 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.
Kohlrabi Planting Timeline — Southeast Fairbanks, AK
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 25 | Apr 25 – May 9 |
| Transplant Outdoors | June 6 | Jun 6 – Jun 20 |
| Direct Sow | May 30 | May 30 – Jun 20 |
| Harvest | July 25 | Jul 25 – Aug 29 |
| Fall Sowing | May 25 | May 25 – Jun 8 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Direct Sow Fall Sowing |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 2a
📆 Growing Season
72 days in Southeast Fairbanks
Growing Tips for Kohlrabi in Southeast Fairbanks
Direct sow Kohlrabi outdoors after June 06 in Southeast Fairbanks when soil has warmed and frost danger has passed.
Common pests for Kohlrabi 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 spring or fall. Harvest when bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Kohlrabi in Other Locations
Frequently Asked Questions
When should I plant Kohlrabi in Southeast Fairbanks, AK?
Southeast Fairbanks is in Zone 2a with an average last frost of June 6. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Southeast Fairbanks, AK?
Southeast Fairbanks, Alaska is in USDA Hardiness Zone 2a. The average last spring frost is June 6 and first fall frost is August 17.
Your Southeast Fairbanks Garden Planner — Free
A 24-page printable planner built for Southeast Fairbanks (Zone 2a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.