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When to Plant Tomatillo in Coos County, OR

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

Coos County, Oregon is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 19, giving you a growing season of approximately 242 days.

At an elevation of 96 feet, Coos County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Tomatillo during the growing season.

Coos County, OR (Zone 8b) Long season
242 days
Last Spring Frost March 22
242 growing days
First Fall Frost November 19

Coos County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (92 days to spare)
Start indoors: Jan 17 Transplant: Mar 21 🍅 Harvest: May 23 – Aug 1
Recommended (50%) ✓ Fits season (95 days to spare)
Start indoors: Feb 1 Transplant: Apr 5 🍅 Harvest: Jun 7 – Aug 16
Safe Start (90%) ✓ Fits season (90 days to spare)
Start indoors: Mar 4 Transplant: May 6 🍅 Harvest: Jul 8 – Sep 16

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 Coos County

How your county's soil matches Tomatillo's growing requirements.

Soil pH

Your soil pH (5.4โ€“6.8) overlaps with Tomatillo's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Coos County is excellent for Tomatillo โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.7%) โ€” Tomatillo will thrive.

How to Plant Tomatillo

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Tomatillo

4
successive plantings in your 242-day season

Sow every 6.9 weeks. Last sowing by Aug 26 to harvest before frost.

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.7″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 919 gal / 100 sq ft

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 โ€” 5.5" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 4.8" 4.4" 0.4" ๐Ÿ’ง Light watering
Apr 4.8" 3.1" 1.7" ๐Ÿ’ง Light watering
May 4.8" 2.3" 2.5" ๐Ÿšฟ Regular watering
Jun 4.8" 1.6" 3.2" ๐Ÿšฟ Regular watering
Jul 4.8" 0.6" 4.2" ๐Ÿšฟ Regular watering
Aug 4.8" 0.8" 4" ๐Ÿšฟ Regular watering
Sep 4.8" 1.4" 3.4" ๐Ÿšฟ Regular watering
Oct 4.8" 3.3" 1.5" ๐Ÿ’ง Light watering
Nov 4.8" 5.9" 0" โœ… Rainfall sufficient
Dec โ€” 5.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Coos County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~1,214 GDD — county provides 4,053 GDD Excellent fit

Tomatillo Planting Timeline โ€” Coos County, OR

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors February 1 Feb 1 โ€“ Feb 15
Transplant Outdoors April 5 Apr 5 โ€“ Apr 19
Direct Sow March 29 Mar 29 โ€“ Apr 19
Harvest June 7 Jun 7 โ€“ Aug 16

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Direct Sow
April Transplant Outdoors Direct Sow
May โ€”
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“85 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

242 days in Coos County

Growing Tips for Tomatillo in Coos County

Direct sow Tomatillo outdoors after March 22 in Coos 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

  • Fennel
  • Dill

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Tomatillo in Coos County, OR?

Coos County is in Zone 8b with an average last frost of March 22. Plan your Tomatillo planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Coos County, OR?

Coos County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Coos County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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