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When to Plant Squash (Summer) in Glenn County, CA

Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.

Glenn County, California is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 28, giving you a growing season of approximately 267 days.

At an elevation of 270 feet, Glenn County receives approximately 27.1 inches of rainfall annually with predominantly loam soil. Summer highs average 88ยฐF, providing good warmth for Squash (Summer) during the growing season.

Glenn County, CA (Zone 9a) Long season
267 days
Last Spring Frost March 6
267 growing days
First Fall Frost November 28

Glenn County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Start indoors: Jan 26 Transplant: Mar 2 🍅 Harvest: Apr 20 – Jun 22
Recommended (50%) ✓ Fits season (148 days to spare)
Start indoors: Feb 6 Transplant: Mar 13 🍅 Harvest: May 1 – Jul 3
Safe Start (90%) ✓ Fits season (126 days to spare)
Start indoors: Mar 21 Transplant: Apr 25 🍅 Harvest: Jun 13 – Aug 15

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 Glenn County

How your county's soil matches Squash (Summer)'s growing requirements.

Soil pH

Your soil pH (6.5โ€“7.9) overlaps with Squash (Summer)'s range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Glenn County is excellent for Squash (Summer) โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Squash (Summer).

How to Plant Squash (Summer)

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Squash (Summer)

7
successive plantings in your 267-day season

Sow every 5.1 weeks. Last sowing by Sep 24 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,636 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Squash (Summer)

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

Month Squash (Summer) Needs Rainfall You Supplement Action
Jan โ€” 5.6" 0" โ„๏ธ Dormant
Feb โ€” 5.3" 0" โ„๏ธ Dormant
Mar 4.3" 4.4" 0" โœ… Rainfall sufficient
Apr 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
May 4.3" 0.7" 3.6" ๐Ÿšฟ Regular watering
Jun 4.3" 0.1" 4.2" ๐Ÿšฟ Regular watering
Jul 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Aug 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Sep 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Oct 4.3" 1.3" 3" ๐Ÿšฟ Regular watering
Nov 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Dec โ€” 4.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Glenn County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Squash (Summer) 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.

Squash (Summer) needs ~880 GDD — county provides 4,272 GDD Excellent fit

Squash (Summer) Planting Timeline โ€” Glenn County, CA

Squash (Summer) Planting Calendar

Activity When Date Range
Start Indoors February 6 Feb 6 โ€“ Feb 20
Transplant Outdoors March 13 Mar 13 โ€“ Mar 27
Direct Sow March 6 Mar 6 โ€“ Mar 27
Harvest May 1 May 1 โ€“ Jul 3

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

45โ€“65 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

267 days in Glenn County

Growing Tips for Squash (Summer) in Glenn County

Direct sow Squash (Summer) outdoors after March 06 in Glenn County when soil has warmed and frost danger has passed.

Your generous 267.0-day season in Glenn County allows multiple plantings of Squash (Summer). Sow every 22.0 days for continuous harvest.

Common pests for Squash (Summer) in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Squash (Summer) in Glenn County, CA?

Glenn County is in Zone 9a with an average last frost of March 6. Plan your Squash (Summer) planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Glenn County, CA?

Glenn County, California is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 28.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Glenn County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.

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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 Glenn County, CA. Local conditions may vary. Last updated: April 2026.