When to Plant Celery in Butte County, CA
May in the garden — Butte County, California
Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.
-
Get celery seeds going inside
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
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.
Butte County, California is in USDA Zone 9b. The average last spring frost is April 20 and the first fall frost is November 10, giving you a growing season of approximately 204 days.
At an elevation of 144 feet, Butte County receives approximately 44.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Celery during the growing season.
Butte County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.7
Drainage
Well Drained
Plant Planting Risk Windows
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 Butte County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (6.8–7.7) is more alkaline than Celery prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Butte County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Celery is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Celery.
How to Plant Celery
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Celery
Sow every 9.1 weeks. Last sowing by Jul 13 to harvest before frost.
For a dedicated fall crop, sow by Sep 15.
Plant Water Budget
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 | — | 9.7" | 0" | ❄️ Dormant |
| Feb | — | 9.9" | 0" | ❄️ Dormant |
| Mar | — | 6.9" | 0" | ❄️ Dormant |
| Apr | 5.6" | 3" | 2.6" | 💧 Light watering |
| May | 5.6" | 1.1" | 4.5" | 🚿 Regular watering |
| Jun | 5.6" | 0.2" | 5.4" | 🚿 Regular watering |
| Jul | 5.6" | 0" | 5.6" | 🚿 Regular watering |
| Aug | 5.6" | 0" | 5.6" | 🚿 Regular watering |
| Sep | 5.6" | 0.4" | 5.2" | 🚿 Regular watering |
| Oct | 5.6" | 2.1" | 3.5" | 🚿 Regular watering |
| Nov | 5.6" | 3.7" | 1.9" | 💧 Light watering |
| Dec | — | 7.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Butte 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 Planting Timeline — Butte County, CA
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Harvest | July 13 | Jul 13 – Sep 7 |
| Fall Sowing | September 15 | Sep 15 – Sep 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing Harvest |
| October | — |
| 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
204 days in Butte County
Growing Tips for Celery in Butte County
Direct sow Celery outdoors after April 20 in Butte 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
Check more plant combinations with our Companion Planting Checker →
Celery in Other Locations
Frequently Asked Questions
When should I plant Celery in Butte County, CA?
Butte County is in Zone 9b with an average last frost of April 20. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Butte County, CA?
Butte County, California is in USDA Hardiness Zone 9b. The average last spring frost is April 20 and first fall frost is November 10.
Your Butte County Garden Planner — Free
A 24-page printable planner built for Butte 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.