When to Plant Rosemary in Ketchikan Gateway Borough, AK
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.
Ketchikan Gateway Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 25 and the first fall frost is October 19, giving you a growing season of approximately 177 days.
At an elevation of 1,212 feet, Ketchikan Gateway Borough receives approximately 57.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 65°F, so choose short-season varieties of Rosemary to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rosemary root diseases.
Ketchikan Gateway Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.7
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.
Plant Water Budget
Rosemary Planting Timeline — Ketchikan Gateway Borough, AK
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Harvest | July 25 | Jul 25 – Dec 12 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| 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
Low — drought tolerant
Days to Maturity
80–180 days
Soil pH
6 – 7.5
USDA Zone
Zone 7b
Growing Season
177 days
Growing Tips for Ketchikan Gateway Borough
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
Level Up Your Garden
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in Ketchikan Gateway Borough, AK?
Ketchikan Gateway Borough is in Zone 7b with an average last frost of April 25. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Ketchikan Gateway Borough, AK?
Ketchikan Gateway Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 25 and first fall frost is October 19.
Plan Your Garden with Confidence
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