Blog

When to plant Sunflower in Sutter County County,

In Sutter County County, plant Sunflower in spring between February 4 and February 25, once soil temps hold above 50°F. Sutter County County's last frost averages March 4, so aim for a steady week of warm soil before planting. For a fall crop, sow between and — roughly 100 days before the first frost on November 26.

When to Plant Sunflower in Sutter County, CA

Sutter County, California Zone 9b June

June in the garden — Sutter County, California

A quick June briefing for Sutter County, California gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 4
Avg. first frost November 26
Soil temp (4") 85°F
Watering Critical
Pest pressure High
Daylight 14.7 hrs
  1. Pick sunflower

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

A few tasks this June that'll pay off in July
  • First harvests: sunflower

Instant PDF download. No spam, unsubscribe any time.

Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Sutter County, California is in USDA Zone 9b. 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 88°F, providing good warmth for Sunflower during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Sutter County, CA (Zone 9b) Long season
267 days
Last Spring Frost March 4
267 growing days
First Fall Frost November 26
Share this guide:

Sutter County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.7

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (55 days to spare)
Start indoors: Jan 17 Transplant: Jan 10 🌸 Bloom: Apr 4 – Sep 19
Recommended (50%) ✓ Fits season (43 days to spare)
Start indoors: Feb 11 Transplant: Feb 4 🌸 Bloom: Apr 29 – Oct 14
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Apr 6 Transplant: Mar 30 🌸 Bloom: Jun 22 – Dec 7

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 Sunflower's growing requirements.

Soil pH

Your soil pH (6.8–7.7) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Sutter County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Sunflower.

Organic Matter

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

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

4
successive plantings in your 267-day season

Sow every 8 weeks. Last sowing by Aug 18 to harvest before frost.

Sunflower Water Budget

Plant needs
0.5″/week
Rainfall provides
0.3″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 894 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sunflower

Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 4.6" 0" ❄️ Dormant
Feb 4.2" 0" ❄️ Dormant
Mar 2.2" 3.7" 0" ✅ Rainfall sufficient
Apr 2.2" 1.4" 0.8" 💧 Light watering
May 2.2" 0.6" 1.6" 🚿 Regular watering
Jun 2.2" 0.1" 2.1" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.2" 2" 🚿 Regular watering
Oct 2.2" 0.9" 1.3" 🚿 Regular watering
Nov 2.2" 1.8" 0.4" 💧 Light watering
Dec 3.8" 0" ❄️ Dormant

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

Sunflower 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" — every day above 50°F 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.

Sunflower needs ~1,360 GDD — county provides 4,272 GDD Excellent fit

Sunflower Planting Timeline — Sutter County, CA

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 11 Feb 11 – Feb 25
Transplant Outdoors February 4 Feb 4 – Feb 18
Direct Sow February 4 Feb 4 – Feb 25
Bloom April 29 Apr 29 – Oct 14

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Transplant Outdoors Direct Sow
March
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

267 days in Sutter County

Growing Tips for Sunflower in Sutter County

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

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Sutter County receives only 21" of rain annually. Sunflower needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Sutter County, CA?

Sutter County is in Zone 9b with an average last frost of March 4. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sutter County, CA?

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

When should I plant Sunflower in Sutter County County, ?

In Sutter County County, , plant Sunflower after the last frost (around March 4) and before the first frost (around November 26). Best results when soil holds above 50°F.

What growing zone is Sutter County County, for Sunflower?

Sutter County County sits in USDA Zone 9b. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.

Can Sunflower grow in Sutter County County's climate?

Yes — Sunflower grows well in Sutter County County's temperate climate. Sutter County County averages a 267-day frost-free season, with last frost around March 4 and first frost around November 26.

🌱

Your Sutter County Garden Planner — Free

A 22-page printable planner built for Sutter 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.

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 Sutter County, CA. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.