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When to plant Tomatillo in Franklin County, IA

In Zone 5a (Franklin County), direct-sow Tomatillo between May 7 and May 28 for spring, after the April 30 last-frost mark.

When to Plant Tomatillo in Franklin County, IA

Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.

Franklin County, Iowa is in USDA Zone 5a. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.

At an elevation of 1,145 feet, Franklin County receives approximately 41.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Tomatillo to ensure they mature before fall.

Franklin County, IA (Zone 5a) Moderate season
160 days
Last Spring Frost April 30
160 growing days
First Fall Frost October 7

Franklin County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Tomatillo Planting Timeline — Franklin County, IA

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest July 16 Jul 16 – Sep 24

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
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

Moderate — regular watering

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

160 days in Franklin County

Growing Tips for Franklin County

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

  • Fennel
  • Dill

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Tomatillo in Franklin County, IA?

Franklin County is in Zone 5a with an average last frost of April 30. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.

What planting zone is Franklin County, IA?

Franklin County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 30 and first fall frost is October 7.

When should I plant Tomatillo in Franklin County, IA?

In Franklin County, IA, plant Tomatillo after the last frost (around April 30) and before the first frost (around October 7). Best results when soil holds above 50°F.

What growing zone is Franklin County, IA for Tomatillo?

Franklin 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 Franklin County's climate?

Yes — Tomatillo grows well in Franklin County's temperate climate. Franklin County averages a 160-day frost-free season, with last frost around April 30 and first frost around October 7.

🌱

Your Franklin County Garden Planner — Free

A 22-page printable planner built for Franklin 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Franklin County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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