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When to plant Tomatillo in Sullivan County, IN

In Sullivan County, plant Tomatillo in spring between April 25 and May 16, once soil temps hold above 50°F. Sullivan County's last frost averages April 18, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between and — roughly 60–85 days before the first frost on October 17.

When to Plant Tomatillo in Sullivan County, IN

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

Sullivan County, Indiana is in USDA Zone 6b. The average last spring frost is April 18 and the first fall frost is October 17, giving you a growing season of approximately 182 days.

At an elevation of 914 feet, Sullivan County receives approximately 34.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Tomatillo during the growing season.

Sullivan County, IN (Zone 6b) Moderate season
182 days
Last Spring Frost April 18
182 growing days
First Fall Frost October 17

Sullivan County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Monthly Watering Guide for Tomatillo

Tomatillo needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Tomatillo Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.6" 0.7" 💧 Light watering
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 3.5" 0.8" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sullivan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Tomatillo Planting Timeline — Sullivan County, IN

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 – Mar 7
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest July 4 Jul 4 – Sep 12

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Direct Sow
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 6b

📆 Growing Season

182 days in Sullivan County

Growing Tips for Sullivan 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 Sullivan County, IN?

Sullivan County is in Zone 6b with an average last frost of April 18. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sullivan County, IN?

Sullivan County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 18 and first fall frost is October 17.

When should I plant Tomatillo in Sullivan County, IN?

In Sullivan County, IN, plant Tomatillo after the last frost (around April 18) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Sullivan County, IN for Tomatillo?

Sullivan County sits in USDA Zone 6b. Tomatillo grows reliably in zones 4a through 11b, so it's a good fit here.

Can Tomatillo grow in Sullivan County's climate?

Yes — Tomatillo grows well in Sullivan County's temperate climate. Sullivan County averages a 182-day frost-free season, with last frost around April 18 and first frost around October 17.

🌱

Your Sullivan County Garden Planner — Free

A 22-page printable planner built for Sullivan 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.

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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 Sullivan County, IN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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