Blog

When to plant Celery in Willows, CA

Plant Celery in Willows from February 13 to March 6 in spring. Willows sits in USDA Zone 9b, with last frost around March 6 and first frost on November 28. A second sowing from October 3 to October 17 extends the harvest into fall.

When to Plant Celery in Willows, CA

Celery
Glenn County, California Zone 9b June

Your June planting checklist for Glenn County, California

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

Avg. last frost March 6
Avg. first frost November 28
Soil temp (4") 85°F
Watering Critical
Pest pressure High
Daylight 14.8 hrs
  1. It's harvest week for celery

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Before July arrives, get these ready
  • First harvests: celery

Instant PDF download. No spam, unsubscribe any time.

Celery is a marshland plant that requires consistent moisture and cool temperatures to produce crisp, flavorful stalks. It is a rewarding but demanding garden crop.

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

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

Willows Soil Profile

Soil Type

Loam

Soil pH

6.5-7.9

Drainage

Well Drained

Celery Planting Risk Windows

Early Start (70% safe) ✓ Fits season (130 days to spare)
Start indoors: Jan 26 Transplant: Feb 23 🍅 Harvest: May 18 – Jul 13
Recommended (50%) ✓ Fits season (127 days to spare)
Start indoors: Feb 6 Transplant: Mar 6 🍅 Harvest: May 29 – Jul 24
Safe Start (90%) ✓ Fits season (105 days to spare)
Start indoors: Mar 21 Transplant: Apr 18 🍅 Harvest: Jul 11 – Sep 5

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 Willows

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

Soil pH

Your soil pH (6.5–7.9) is more alkaline than Celery prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

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

How to Plant Celery

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Celery

3
successive plantings in your 267-day season

Sow every 9.1 weeks. Last sowing by Jul 31 to harvest before frost.

For a dedicated fall crop, sow by Oct 03.

Celery Water Budget

Plant needs
1.3″/week
Rainfall provides
0.4″/week
You supply
1.1″/week
Watering frequency 2-3 times/week
Season total 2,491 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Celery

Celery needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.

Month Celery Needs Rainfall You Supplement Action
Jan 5.6" 0" ❄️ Dormant
Feb 5.3" 0" ❄️ Dormant
Mar 5.6" 4.4" 1.2" 💧 Light watering
Apr 5.6" 2.5" 3.1" 🚿 Regular watering
May 5.6" 0.7" 4.9" 🚿 Regular watering
Jun 5.6" 0.1" 5.5" 🚿 Regular watering
Jul 5.6" 0" 5.6" 🚿 Regular watering
Aug 5.6" 0" 5.6" 🚿 Regular watering
Sep 5.6" 0.3" 5.3" 🚿 Regular watering
Oct 5.6" 1.3" 4.3" 🚿 Regular watering
Nov 5.6" 2.5" 3.1" 🚿 Regular watering
Dec 4.3" 0" ❄️ Dormant

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

Celery 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.

Celery needs ~1,600 GDD — county provides 4,272 GDD Excellent fit

Celery Planting Timeline — Willows, CA

Celery Planting Calendar

Activity When Date Range
Start Indoors February 6 Feb 6 – Feb 20
Transplant Outdoors March 6 Mar 6 – Mar 20
Direct Sow February 13 Feb 13 – Mar 6
Harvest May 29 May 29 – Jul 24
Fall Sowing October 3 Oct 3 – Oct 17

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.3"/week · 2-3 times/week

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

267 days in Glenn County

Growing Tips for Celery in Willows

Direct sow Celery outdoors after March 06 in Glenn County when soil has warmed and frost danger has passed.

Common pests for Celery in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Keep soil consistently moist and never let it dry out. Blanch stalks by mounding soil or using collars for milder flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

When should I plant Celery in Willows, CA?

In Willows, CA, plant Celery after the last frost (around March 6) and before the first frost (around November 28). Best results when soil holds above 50°F.

What growing zone is Willows, CA for Celery?

Willows sits in USDA Zone 9b. Celery grows reliably in zones 2a through 10b, so it's a good fit here.

Can Celery grow in Willows's climate?

Yes — Celery grows well in Willows's temperate climate. Willows averages a 267-day frost-free season, with last frost around March 6 and first frost around November 28.

🌱

Your Glenn County Garden Planner — Free

A 22-page printable planner built for Glenn 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 Glenn County, CA. Local conditions may vary. Last updated: June 2026.