When to Plant Garlic in Asotin County, WA
Garlic is a pungent allium planted in fall and harvested the following summer. Hardneck varieties produce edible flower stalks (scapes) and are more cold-hardy.
Asotin County, Washington is in USDA Zone 6b. The average last spring frost is May 9 and the first fall frost is September 30, giving you a growing season of approximately 144 days.
At an elevation of 2,029 feet, Asotin County receives approximately 14 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Garlic during the growing season. With low rainfall, drip irrigation is essential for growing Garlic successfully. Mulch heavily to conserve soil moisture.
Asotin County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.5
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 Asotin County
How your county's soil matches Garlic's growing requirements.
Soil pH
Your soil pH (5.5–6.5) overlaps with Garlic's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Asotin County is excellent for Garlic — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.7%) — Garlic will thrive.
How to Plant Garlic
Fall planting: Sow 6 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Garlic
Garlic needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Garlic Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 0.9" | 0" | ❄️ Dormant |
| May | 2.2" | 0.8" | 1.4" | 🚿 Regular watering |
| Jun | 2.2" | 0.6" | 1.6" | 🚿 Regular watering |
| Jul | 2.2" | 0.2" | 2" | 🚿 Regular watering |
| Aug | 2.2" | 0.3" | 1.9" | 🚿 Regular watering |
| Sep | 2.2" | 0.5" | 1.7" | 🚿 Regular watering |
| Oct | — | 1.2" | 0" | ❄️ Dormant |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Asotin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Garlic 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.
Garlic Planting Timeline — Asotin County, WA
Garlic Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Fall Sowing | August 19 | Aug 19 – Sep 2 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
90–240 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
144 days in Asotin County
Growing Tips for Garlic in Asotin County
Direct sow Garlic outdoors after May 09 in Asotin County when soil has warmed and frost danger has passed.
Your 144.0-day growing season in Asotin County is tight for Garlic (90.0-240.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Garlic in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant individual cloves pointed end up in fall, 6 weeks before ground freezes. Mulch heavily with straw. Harvest when lower leaves begin to brown but 5-6 green leaves remain.
Companion Planting
Good Companions
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Garlic in Other Locations
Frequently Asked Questions
When should I plant Garlic in Asotin County, WA?
Asotin County is in Zone 6b with an average last frost of May 9. Plan your Garlic planting based on this frost date — see the calendar above for exact timing.
What planting zone is Asotin County, WA?
Asotin County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 9 and first fall frost is September 30.
Plan Your Garden with Confidence
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