When to Plant Lavender in Island 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.
Island County, Washington is in USDA Zone 8a. The average last spring frost is March 30 and the first fall frost is November 3, giving you a growing season of approximately 218 days.
At an elevation of 9 feet, Island County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lavender during the growing season.
Island County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
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.
Soil Compatibility in Island County
How your county's soil matches Lavender's growing requirements.
Soil pH
Your soil pH (5.6–6.7) is more acidic than Lavender prefers (6.5–8.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Island County is excellent for Lavender — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.3%) — Lavender will thrive.
How to Plant Lavender
Plant Water Budget
Monthly Watering Guide for Lavender
Lavender 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 | Lavender Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.8" | 0" | ❄️ Dormant |
| Feb | — | 4.7" | 0" | ❄️ Dormant |
| Mar | 1.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Apr | 1.3" | 3.7" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 2.3" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 1.6" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 0.7" | 0.6" | 💧 Light watering |
| Aug | 1.3" | 0.8" | 0.5" | 💧 Light watering |
| Sep | 1.3" | 1.6" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Nov | 1.3" | 7" | 0" | ✅ Rainfall sufficient |
| Dec | — | 7.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Island County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lavender 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.
Lavender Planting Timeline — Island County, WA
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Harvest | July 6 | Jul 6 – Dec 7 |
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
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
90–200 days
🧪 Soil pH
Needs 6.5–8 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
218 days in Island County
Growing Tips for Lavender in Island County
Direct sow Lavender outdoors after March 30 in Island County when soil has warmed and frost danger has passed.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Lavender in Other Locations
Frequently Asked Questions
When should I plant Lavender in Island County, WA?
Island County is in Zone 8a with an average last frost of March 30. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is Island County, WA?
Island County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 30 and first fall frost is November 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Island County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.
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