When to Plant Tomatillo in Cassia County, ID
Your May gardening checklist
A quick May briefing for Cassia County, Idaho gardeners — what's urgent, what's next, and what can wait.
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Move tomatillo into the garden
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
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Scatter tomatillo into prepared beds
Your soil is 35°F — warm enough for these to germinate without babying.
Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.
Cassia County, Idaho is in USDA Zone 6b. The average last spring frost is May 15 and the first fall frost is October 1, giving you a growing season of approximately 139 days.
At an elevation of 8,089 feet, Cassia County receives approximately 17.5 inches of rainfall annually with predominantly loam soil. Summer highs average 87°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.
Cassia County Soil Profile
Soil Type
Loam
Soil pH
6.3-8.2
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 Cassia County
How your county's soil matches Tomatillo's growing requirements.
Soil pH
Your soil pH (6.3–8.2) is more alkaline than Tomatillo prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Cassia County is excellent for Tomatillo — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Tomatillo.
How to Plant Tomatillo
Succession Planting Tomatillo
Sow every 6.9 weeks. Last sowing by Jul 08 to harvest before frost.
Plant Water Budget
Water stress score is 8/10 — 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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 1.8" | 0" | ❄️ Dormant |
| May | 4.8" | 2.3" | 2.5" | 🚿 Regular watering |
| Jun | 4.8" | 1.1" | 3.7" | 🚿 Regular watering |
| Jul | 4.8" | 1.5" | 3.3" | 🚿 Regular watering |
| Aug | 4.8" | 1.7" | 3.1" | 🚿 Regular watering |
| Sep | 4.8" | 1.3" | 3.5" | 🚿 Regular watering |
| Oct | 4.8" | 1.6" | 3.2" | 🚿 Regular watering |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Cassia 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 — Cassia County, ID
Tomatillo Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 20 | Mar 20 – Apr 3 |
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Direct Sow | May 22 | May 22 – Jun 12 |
| Harvest | July 31 | Jul 31 – Oct 9 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| 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 · 1-2 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6b
📆 Growing Season
139 days in Cassia County
Growing Tips for Tomatillo in Cassia County
Direct sow Tomatillo outdoors after May 15 in Cassia 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.
Cassia County receives only 18" 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 Cassia County, ID?
Cassia County is in Zone 6b with an average last frost of May 15. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cassia County, ID?
Cassia County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 15 and first fall frost is October 1.
Your Cassia County Garden Planner — Free
A 24-page printable planner built for Cassia County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.