When to plant Tomatillo in Linn County, IA
Plant Tomatillo in Linn County after April 25; the prime window is May 2–May 23.
When to Plant Tomatillo in Linn County, IA
June in the garden — Linn County, Iowa
June is a pivotal month for Linn County, Iowa gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Start tomatillo under lights
Your window is short. These crops want several weeks of indoor growth before they go outside.
July prep starts now
- First harvests: tomatillo
Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.
Linn County, Iowa is in USDA Zone 5a. The average last spring frost is April 25 and the first fall frost is October 11, giving you a growing season of approximately 169 days.
At an elevation of 938 feet, Linn County receives approximately 36.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Tomatillo to ensure they mature before fall.
Linn County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.2
Drainage
Well Drained
Tomatillo 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 Linn County
How your county's soil matches Tomatillo's growing requirements.
Soil pH
Your soil pH (5.7–7.2) overlaps with Tomatillo's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Linn County is excellent for Tomatillo — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Tomatillo.
Organic Matter
Organic matter is excellent (4.5%) — Tomatillo will thrive.
How to Plant Tomatillo
Succession Planting Tomatillo
Sow every 6.9 weeks. Last sowing by Jul 18 to harvest before frost.
Tomatillo 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 4.8" | 3.3" | 1.5" | 💧 Light watering |
| May | 4.8" | 4.3" | 0.5" | 💧 Light watering |
| Jun | 4.8" | 4.2" | 0.6" | 💧 Light watering |
| Jul | 4.8" | 3.9" | 0.9" | 💧 Light watering |
| Aug | 4.8" | 4.3" | 0.5" | 💧 Light watering |
| Sep | 4.8" | 3.4" | 1.4" | 💧 Light watering |
| Oct | 4.8" | 3" | 1.8" | 💧 Light watering |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Linn 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 — Linn County, IA
Tomatillo Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 28 | Feb 28 – Mar 14 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Direct Sow | May 2 | May 2 – May 23 |
| Harvest | July 11 | Jul 11 – Sep 19 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| 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: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
169 days in Linn County
Growing Tips for Tomatillo in Linn County
Direct sow Tomatillo outdoors after April 25 in Linn 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.
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 Linn County, IA?
Linn County is in Zone 5a with an average last frost of April 25. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.
What planting zone is Linn County, IA?
Linn County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 25 and first fall frost is October 11.
When should I plant Tomatillo in Linn County, IA?
In Linn County, IA, plant Tomatillo after the last frost (around April 25) and before the first frost (around October 11). Best results when soil holds above 50°F.
What growing zone is Linn County, IA for Tomatillo?
Linn County sits in USDA Zone 5a. Tomatillo grows reliably in zones 4a through 11b, so it's a good fit here.
Can Tomatillo grow in Linn County's climate?
Yes — Tomatillo grows well in Linn County's temperate climate. Linn County averages a 169-day frost-free season, with last frost around April 25 and first frost around October 11.
Your Linn County Garden Planner — Free
A 22-page printable planner built for Linn County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.