When to Plant Tomatillo in Adams County, WA
Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.
Adams County, Washington is in USDA Zone 6b. The average last spring frost is May 7 and the first fall frost is October 3, giving you a growing season of approximately 149 days.
At an elevation of 2,402 feet, Adams County receives approximately 17.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Tomatillo during the growing season. With low rainfall, drip irrigation is essential for growing Tomatillo successfully. Mulch heavily to conserve soil moisture.
Adams County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.4
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.
Soil Compatibility in Adams County
How your county's soil matches Tomatillo's growing requirements.
Soil pH
Your soil pH (5.7–6.4) overlaps with Tomatillo's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Adams County is excellent for Tomatillo — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.3%) — Tomatillo will thrive.
How to Plant Tomatillo
Succession Planting Tomatillo
Sow every 6.9 weeks. Last sowing by Jul 10 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Tomatillo
Tomatillo needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatillo Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.7" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | 4.8" | 0.8" | 4" | 🚿 Regular watering |
| Jun | 4.8" | 0.6" | 4.2" | 🚿 Regular watering |
| Jul | 4.8" | 0.3" | 4.5" | 🚿 Regular watering |
| Aug | 4.8" | 0.4" | 4.4" | 🚿 Regular watering |
| Sep | 4.8" | 0.6" | 4.2" | 🚿 Regular watering |
| Oct | 4.8" | 1.6" | 3.2" | 🚿 Regular watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Adams County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatillo 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.
Tomatillo Planting Timeline — Adams County, WA
Tomatillo Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | May 21 | May 21 – Jun 4 |
| Direct Sow | May 14 | May 14 – Jun 4 |
| Harvest | July 23 | Jul 23 – Oct 1 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.1"/week · 2-3 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
149 days in Adams County
Growing Tips for Tomatillo in Adams County
Direct sow Tomatillo outdoors after May 07 in Adams County when soil has warmed and frost danger has passed.
Common pests for Tomatillo in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
Adams County receives only 17" of rain annually. Tomatillo needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Plant at least two plants for cross-pollination. Harvest when fruits fill the husk and it begins to split.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Tomatillo in Other Locations
Frequently Asked Questions
When should I plant Tomatillo in Adams County, WA?
Adams County is in Zone 6b with an average last frost of May 7. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.
What planting zone is Adams County, WA?
Adams County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 7 and first fall frost is October 3.
Plan Your Garden with Confidence
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