When to Plant Rosemary in Sitka City and Borough, AK
This month in Sitka City and Borough, Alaska
Each item below is timed to Sitka City and Borough, Alaska's frost dates and soil temperatures. Skip nothing, stress about nothing.
Rosemary is an aromatic evergreen shrub with needle-like leaves and a piney, citrus flavor. It is a Mediterranean herb that thrives in warm, dry conditions.
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 Rosemary 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 Rosemary's growing requirements.
Soil pH
Your soil pH (4.9–6.4) is more acidic than Rosemary 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 Rosemary — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Rosemary will thrive.
How to Plant Rosemary
Succession Planting Rosemary
Sow every 9.1 weeks. Last sowing by Apr 27 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Rosemary
Rosemary needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.
| Month | Rosemary Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 0.7" | 0" | ❄️ Dormant |
| Apr | 1.3" | 0.6" | 0.7" | 🚿 Regular watering |
| May | 1.3" | 1.1" | 0.2" | 💧 Light watering |
| Jun | 1.3" | 1.5" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 2.8" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 2.9" | 0" | ✅ Rainfall sufficient |
| 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.
Rosemary 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.
Rosemary Planting Timeline — Sitka City and Borough, AK
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Harvest | July 20 | Jul 20 – Dec 7 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | Harvest |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
80–180 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 Rosemary in Sitka City and Borough
Direct sow Rosemary outdoors after April 20 in Sitka City and Borough when soil has warmed and frost danger has passed.
Your 187.0-day growing season in Sitka City and Borough is tight for Rosemary (80.0-180.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Grow in well-drained soil and avoid overwatering. In cold climates, grow in containers and bring indoors for winter. Propagate from stem cuttings for faster results than seed.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in Sitka City and Borough, AK?
Sitka City and Borough is in Zone 7b with an average last frost of April 20. Plan your Rosemary 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.