When to Plant Lavender in Glenn County, CA
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.
Glenn County, California is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 28, giving you a growing season of approximately 267 days.
At an elevation of 270 feet, Glenn County receives approximately 27.1 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Lavender during the growing season.
Glenn County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.9
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 Glenn County
How your county's soil matches Lavender's growing requirements.
Soil pH
Your soil pH (6.5–7.9) is within Lavender's preferred range (6.5–8.0).
Soil Texture
The loam soil in Glenn County is excellent for Lavender — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Lavender.
How to Plant Lavender
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
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 | — | 5.6" | 0" | ❄️ Dormant |
| Feb | — | 5.3" | 0" | ❄️ Dormant |
| Mar | 1.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 1.3" | 2.5" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 0.7" | 0.6" | 💧 Light watering |
| Jun | 1.3" | 0.1" | 1.2" | 🚿 Regular watering |
| Jul | 1.3" | 0" | 1.3" | 🚿 Regular watering |
| Aug | 1.3" | 0" | 1.3" | 🚿 Regular watering |
| Sep | 1.3" | 0.3" | 1" | 🚿 Regular watering |
| Oct | 1.3" | 1.3" | 0" | ✅ Rainfall sufficient |
| Nov | 1.3" | 2.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Glenn 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 — Glenn County, CA
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 13 | Mar 13 – Mar 27 |
| Harvest | June 12 | Jun 12 – Nov 13 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
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: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
267 days in Glenn County
Growing Tips for Lavender in Glenn County
Direct sow Lavender outdoors after March 06 in Glenn 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 Glenn County, CA?
Glenn County is in Zone 9a with an average last frost of March 6. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is Glenn County, CA?
Glenn County, California is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 28.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Glenn County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
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