When to Plant Brussels Sprouts in Sitka City and Borough, AK
Sitka City and Borough, Alaska gardeners: here's your May plan
Each item below is timed to Sitka City and Borough, Alaska's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Sow brussels sprouts in trays indoors
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
Brussels sprouts are a cold-hardy brassica that produces miniature cabbage-like heads along a tall stalk. Flavor improves after a light frost.
Sitka City and Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 20 and the first fall frost is October 24, giving you a growing season of approximately 187 days.
At an elevation of 1,935 feet, Sitka City and Borough receives approximately 21.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 69°F, so choose short-season varieties of Brussels Sprouts to ensure they mature before fall.
Sitka City and Borough Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.4
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 Sitka City and Borough
How your county's soil matches Brussels Sprouts's growing requirements.
Soil pH
Your soil pH (4.9–6.4) is more acidic than Brussels Sprouts prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Sitka City and Borough is excellent for Brussels Sprouts — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Brussels Sprouts will thrive.
How to Plant Brussels Sprouts
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Brussels Sprouts
Brussels Sprouts needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Brussels Sprouts Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 0.7" | 0" | ❄️ Dormant |
| Apr | 3.9" | 0.6" | 3.3" | 🚿 Regular watering |
| May | 3.9" | 1.1" | 2.8" | 🚿 Regular watering |
| Jun | 3.9" | 1.5" | 2.4" | 🚿 Regular watering |
| Jul | 3.9" | 2.8" | 1.1" | 💧 Light watering |
| Aug | 3.9" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3.9" | 3.5" | 0.4" | 💧 Light watering |
| Oct | 3.9" | 2.9" | 1" | 💧 Light watering |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Sitka City and Borough). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Brussels Sprouts 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.
Brussels Sprouts Planting Timeline — Sitka City and Borough, AK
Brussels Sprouts Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 16 | Mar 16 – Mar 30 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 6 | Apr 6 – Apr 27 |
| Harvest | July 20 | Jul 20 – Sep 14 |
| Fall Sowing | August 15 | Aug 15 – Aug 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · 1-2 times/week
📅 Days to Maturity
90–130 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
187 days in Sitka City and Borough
Growing Tips for Brussels Sprouts in Sitka City and Borough
Direct sow Brussels Sprouts outdoors after April 20 in Sitka City and Borough when soil has warmed and frost danger has passed.
Common pests for Brussels Sprouts in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
Sitka City and Borough receives only 22" of rain annually. Brussels Sprouts needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 12-14 weeks before first fall frost. Stake tall plants to prevent toppling. Remove lower leaves as sprouts develop to improve air circulation.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Brussels Sprouts in Other Locations
Frequently Asked Questions
When should I plant Brussels Sprouts in Sitka City and Borough, AK?
Sitka City and Borough is in Zone 7b with an average last frost of April 20. Plan your Brussels Sprouts planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sitka City and Borough, AK?
Sitka City and Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 20 and first fall frost is October 24.
Your Sitka City and Borough Garden Planner — Free
A 24-page printable planner built for Sitka 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.