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When to Plant Basil in Sutter County, CA

Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

Sutter County, California is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 26, giving you a growing season of approximately 267 days.

At an elevation of 484 feet, Sutter County receives approximately 21.4 inches of rainfall annually with predominantly loam soil. Summer highs average 88ยฐF, providing good warmth for Basil during the growing season.

Sutter County, CA (Zone 9a) Long season
267 days
Last Spring Frost March 4
267 growing days
First Fall Frost November 26

Sutter County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (153 days to spare)
Start indoors: Dec 27 Transplant: Feb 14 🍅 Harvest: Apr 11 – Jun 13
Recommended (50%) ✓ Fits season (141 days to spare)
Start indoors: Jan 21 Transplant: Mar 11 🍅 Harvest: May 6 – Jul 8
Safe Start (90%) ✓ Fits season (108 days to spare)
Start indoors: Mar 16 Transplant: May 4 🍅 Harvest: Jun 29 – Aug 31

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 Sutter County

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

Soil pH

Your soil pH (6.8โ€“7.7) is more alkaline than Basil prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Basil.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Basil.

How to Plant Basil

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Basil

6
successive plantings in your 267-day season

Sow every 5.7 weeks. Last sowing by Sep 12 to harvest before frost.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.3″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,264 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Basil

Basil needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Basil Needs Rainfall You Supplement Action
Jan โ€” 4.6" 0" โ„๏ธ Dormant
Feb โ€” 4.2" 0" โ„๏ธ Dormant
Mar 2.6" 3.7" 0" โœ… Rainfall sufficient
Apr 2.6" 1.4" 1.2" ๐Ÿ’ง Light watering
May 2.6" 0.6" 2" ๐Ÿšฟ Regular watering
Jun 2.6" 0.1" 2.5" ๐Ÿšฟ Regular watering
Jul 2.6" 0" 2.6" ๐Ÿšฟ Regular watering
Aug 2.6" 0" 2.6" ๐Ÿšฟ Regular watering
Sep 2.6" 0.2" 2.4" ๐Ÿšฟ Regular watering
Oct 2.6" 0.9" 1.7" ๐Ÿšฟ Regular watering
Nov 2.6" 1.8" 0.8" ๐Ÿ’ง Light watering
Dec โ€” 3.8" 0" โ„๏ธ Dormant

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

Basil 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.

Basil needs ~1,000 GDD — county provides 4,272 GDD Excellent fit

Basil Planting Timeline โ€” Sutter County, CA

Basil Planting Calendar

Activity When Date Range
Start Indoors January 21 Jan 21 โ€“ Feb 4
Transplant Outdoors March 11 Mar 11 โ€“ Mar 25
Direct Sow March 11 Mar 11 โ€“ Apr 1
Harvest May 6 May 6 โ€“ Jul 8

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors Direct Sow
April Direct Sow
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

0.6"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

50โ€“75 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

267 days in Sutter County

Growing Tips for Basil in Sutter County

Direct sow Basil outdoors after March 04 in Sutter County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Sutter County, CA?

Sutter County is in Zone 9a with an average last frost of March 4. Plan your Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Sutter County, CA?

Sutter County, California is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Sutter County gardeners in Zone 9a 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 Sutter County, CA. Local conditions may vary. Last updated: April 2026.