Blog

When to plant Tomatillo in Berkeley, IL

Berkeley's climate puts the Tomatillo spring window between April 30 and May 21. time plantings around the expected last-frost window for best survival.

When to Plant Tomatillo in Berkeley, IL

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

Berkeley, Illinois is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 17, giving you a growing season of approximately 177 days.

At an elevation of 728 feet, Cook County receives approximately 35.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Tomatillo during the growing season.

Berkeley, IL (Zone 6a) Moderate season
177 days
Last Spring Frost April 23
177 growing days
First Fall Frost October 17

Berkeley 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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 3.2" 1.1" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Tomatillo Planting Timeline — Berkeley, IL

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors May 7 May 7 – May 21
Direct Sow April 30 Apr 30 – May 21
Harvest July 9 Jul 9 – Sep 17

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 6a

📆 Growing Season

177 days in Cook County

Growing Tips for Berkeley

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 →

When should I plant Tomatillo in Berkeley, IL?

In Berkeley, IL, plant Tomatillo after the last frost (around April 23) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Berkeley, IL for Tomatillo?

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

Can Tomatillo grow in Berkeley's climate?

Yes — Tomatillo grows well in Berkeley's temperate climate. Berkeley averages a 177-day frost-free season, with last frost around April 23 and first frost around October 17.

🌱

Your Cook County Garden Planner — Free

A 22-page printable planner built for Cook County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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