When to Plant Lavender in San Juan County, WA
Lavender is a fragrant perennial herb with silvery foliage and purple flower spikes. It is prized for its essential oils, culinary uses, and ornamental beauty.
San Juan County, Washington is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 3, giving you a growing season of approximately 222 days.
At an elevation of 371 feet, San Juan County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Lavender to ensure they mature before fall.
San Juan County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.4
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.
Plant Water Budget
Lavender Planting Timeline — San Juan County, WA
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 2 | Apr 2 – Apr 16 |
| Harvest | July 2 | Jul 2 – Dec 3 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| 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
90–200 days
Soil pH
6.5 – 8
USDA Zone
Zone 8a
Growing Season
222 days
Growing Tips for San Juan County
Plant in well-drained, sandy soil. Avoid heavy mulching around the crown. Prune after flowering but do not cut into old wood. Lavender resents wet winter conditions.
Companion Planting
Good Companions
Level Up Your Garden
Lavender in Other Locations
Frequently Asked Questions
When should I plant Lavender in San Juan County, WA?
San Juan County is in Zone 8a with an average last frost of March 26. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Juan County, WA?
San Juan County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help San Juan County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.
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