When to Plant Celery in San Francisco County, CA
Your May gardening checklist
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in San Francisco County, California.
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Basket week: celery
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
Before June arrives, get these ready
- First harvests: celery
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.
San Francisco County, California is in USDA Zone 10b. The average last spring frost is February 23 and the first fall frost is November 27, giving you a growing season of approximately 277 days.
At an elevation of 412 feet, San Francisco County receives approximately 13.5 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Celery during the growing season. With low rainfall, drip irrigation is essential for growing Celery successfully. Mulch heavily to conserve soil moisture.
San Francisco County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.2
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 San Francisco County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (6.2–7.2) overlaps with Celery's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in San Francisco 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
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 30 to harvest before frost.
For a dedicated fall crop, sow by Oct 02.
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 | — | 2.3" | 0" | ❄️ Dormant |
| Feb | 5.6" | 3.1" | 2.5" | 💧 Light watering |
| Mar | 5.6" | 2.2" | 3.4" | 🚿 Regular watering |
| Apr | 5.6" | 1.2" | 4.4" | 🚿 Regular watering |
| May | 5.6" | 0.3" | 5.3" | 🚿 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" | 0.1" | 5.5" | 🚿 Regular watering |
| Oct | 5.6" | 0.6" | 5" | 🚿 Regular watering |
| Nov | 5.6" | 1.4" | 4.2" | 🚿 Regular watering |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in San Francisco 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 — San Francisco County, CA
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 26 | Jan 26 – Feb 9 |
| Transplant Outdoors | February 23 | Feb 23 – Mar 9 |
| Direct Sow | February 2 | Feb 2 – Feb 23 |
| Harvest | May 18 | May 18 – Jul 13 |
| Fall Sowing | October 2 | Oct 2 – Oct 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors |
| 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: acceptable
🗺️ USDA Zone
Zone 10b
📆 Growing Season
277 days in San Francisco County
Growing Tips for Celery in San Francisco County
Direct sow Celery outdoors after February 23 in San Francisco 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.
San Francisco County receives only 14" of rain annually. Celery needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 San Francisco County, CA?
San Francisco County is in Zone 10b with an average last frost of February 23. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Francisco County, CA?
San Francisco County, California is in USDA Hardiness Zone 10b. The average last spring frost is February 23 and first fall frost is November 27.
Your San Francisco County Garden Planner — Free
A 24-page printable planner built for San Francisco County (Zone 10b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.