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When to plant Tomatillo in Pima County, AZ

Pima County's spring Tomatillo window runs April 1 through April 22. aim for a steady week of warm soil before planting.

When to Plant Tomatillo in Pima County, AZ

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

Pima County, Arizona is in USDA Zone 9b. The average last spring frost is April 1 and the first fall frost is November 9, giving you a growing season of approximately 222 days.

At an elevation of 4,327 feet, Pima County receives approximately 14.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103°F, so Tomatillo may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Tomatillo will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Tomatillo successfully. Mulch heavily to conserve soil moisture.

Pima County, AZ (Zone 9b) Long season
222 days
Last Spring Frost April 1
222 growing days
First Fall Frost November 9

Pima County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.8-8.3

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 0.9" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 0.7" 0" ❄️ Dormant
Apr 4.3" 0.5" 3.8" 🚿 Regular watering
May 4.3" 0.4" 3.9" 🚿 Regular watering
Jun 4.3" 0.5" 3.8" 🚿 Regular watering
Jul 4.3" 2.7" 1.6" 💧 Light watering
Aug 4.3" 3.2" 1.1" 💧 Light watering
Sep 4.3" 1.9" 2.4" 🚿 Regular watering
Oct 4.3" 1.4" 2.9" 🚿 Regular watering
Nov 4.3" 0.7" 3.6" 🚿 Regular watering
Dec 0.9" 0" ❄️ Dormant

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

Tomatillo Planting Timeline — Pima County, AZ

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow April 1 Apr 1 – Apr 22
Harvest June 10 Jun 10 – Aug 19

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May
June Harvest
July Harvest
August Harvest
September
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 9b

📆 Growing Season

222 days in Pima County

Growing Tips for Pima 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 Pima County, AZ?

Pima County is in Zone 9b with an average last frost of April 1. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.

What planting zone is Pima County, AZ?

Pima County, Arizona is in USDA Hardiness Zone 9b. The average last spring frost is April 1 and first fall frost is November 9.

When should I plant Tomatillo in Pima County, AZ?

In Pima County, AZ, plant Tomatillo after the last frost (around April 1) and before the first frost (around November 9). Best results when soil holds above 50°F.

What growing zone is Pima County, AZ for Tomatillo?

Pima County sits in USDA Zone 9b. Tomatillo grows reliably in zones 4a through 11b, so it's a good fit here.

Can Tomatillo grow in Pima County's climate?

Yes — Tomatillo grows well in Pima County's temperate climate. Pima County averages a 222-day frost-free season, with last frost around April 1 and first frost around November 9.

🌱

Your Pima County Garden Planner — Free

A 22-page printable planner built for Pima County (Zone 9b). 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 Pima County, AZ. Local conditions may vary. Last updated: June 2026.

Sources & credits

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