When to Plant Kohlrabi in Denali Borough, AK
May in Denali Borough, Alaska — your action list
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Denali Borough, Alaska.
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Sow kohlrabi where they'll grow
Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.
Before June arrives, get these ready
- Transplants going out: kohlrabi
- Fall sowing: 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.
Denali Borough, Alaska is in USDA Zone 2a. The average last spring frost is June 2 and the first fall frost is August 25, giving you a growing season of approximately 84 days.
At an elevation of 2,930 feet, Denali Borough receives approximately 15.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 70°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Kohlrabi successfully. Mulch heavily to conserve soil moisture.
Denali Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.6
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 Denali Borough
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (5.2–6.6) is more acidic than Kohlrabi prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Denali Borough is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Kohlrabi.
Organic Matter
Organic matter is excellent (6.0%) — Kohlrabi will thrive.
How to Plant Kohlrabi
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Kohlrabi
Sow every 5.1 weeks. Last sowing by Jun 21 to harvest before frost.
For a dedicated fall crop, sow by Jun 02.
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 | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.6" | 0" | ❄️ Dormant |
| Mar | — | 0.6" | 0" | ❄️ Dormant |
| Apr | — | 0.5" | 0" | ❄️ Dormant |
| May | — | 0.7" | 0" | ❄️ Dormant |
| Jun | 3" | 1.3" | 1.7" | 🚿 Regular watering |
| Jul | 3" | 1.7" | 1.3" | 💧 Light watering |
| Aug | 3" | 2.7" | 0.3" | 💧 Light watering |
| Sep | — | 2.8" | 0" | ❄️ Dormant |
| Oct | — | 2" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Aug in Denali Borough). 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 — Denali Borough, AK
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 21 | Apr 21 – May 5 |
| Transplant Outdoors | June 2 | Jun 2 – Jun 16 |
| Direct Sow | May 26 | May 26 – Jun 16 |
| Harvest | July 21 | Jul 21 – Aug 25 |
| Fall Sowing | June 2 | Jun 2 – Jun 16 |
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 |
| 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
84 days in Denali Borough
Growing Tips for Kohlrabi in Denali Borough
Direct sow Kohlrabi outdoors after June 02 in Denali Borough 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 Denali Borough, AK?
Denali Borough is in Zone 2a with an average last frost of June 2. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Denali Borough, AK?
Denali Borough, Alaska is in USDA Hardiness Zone 2a. The average last spring frost is June 2 and first fall frost is August 25.
Your Denali Borough Garden Planner — Free
A 24-page printable planner built for Denali Borough (Zone 2a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.