When to Plant Kohlrabi in Wrangell City and Borough, AK
May in the garden — Wrangell City and Borough, Alaska
Welcome to May in Zone 7b. These are the moves that will have the biggest impact on your growing season.
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Indoor seed-starting week for kohlrabi
These need a head start before your last frost (April 23). Sow into cells now so you're ready to transplant in a few weeks.
Before June arrives, get these ready
- First harvests: 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.
Wrangell City and Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 23 and the first fall frost is October 20, giving you a growing season of approximately 180 days.
At an elevation of 1,533 feet, Wrangell City and Borough receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 59°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall.
Wrangell City and Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.5
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 Wrangell City and Borough
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (5.1–6.5) is more acidic than Kohlrabi prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Wrangell City and 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 (6.1%) — Kohlrabi will thrive.
How to Plant Kohlrabi
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kohlrabi
Sow every 5.1 weeks. Last sowing by Aug 16 to harvest before frost.
For a dedicated fall crop, sow by Aug 11.
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 | — | 1.9" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | 3" | 1.1" | 1.9" | 🚿 Regular watering |
| May | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Jun | 3" | 2.9" | 0.1" | 💧 Light watering |
| Jul | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 6.2" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Wrangell City and 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 — Wrangell City and Borough, AK
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Harvest | June 11 | Jun 11 – Jul 16 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| 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 7b
📆 Growing Season
180 days in Wrangell City and Borough
Growing Tips for Kohlrabi in Wrangell City and Borough
Direct sow Kohlrabi outdoors after April 23 in Wrangell City and Borough when soil has warmed and frost danger has passed.
Your generous 180.0-day season in Wrangell City and Borough allows multiple plantings of Kohlrabi. Sow every 22.0 days for continuous harvest.
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 Wrangell City and Borough, AK?
Wrangell City and Borough is in Zone 7b with an average last frost of April 23. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Wrangell City and Borough, AK?
Wrangell City and Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 23 and first fall frost is October 20.
Your Wrangell City and Borough Garden Planner — Free
A 24-page printable planner built for Wrangell City and Borough (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.