When to plant Celery in Riverside County, CA
For Riverside County, gardeners: plant Celery February 3 through February 24 once soil reads 50°F. A second sowing from October 9 to October 23 extends the harvest into fall.
When to Plant Celery in Riverside County, CA
This month in Riverside County, California
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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Basket week: celery
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
To set up a strong July, finish these tasks
- 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.
Riverside County, California is in USDA Zone 10a. The average last spring frost is February 24 and the first fall frost is December 4, giving you a growing season of approximately 283 days.
At an elevation of 1,206 feet, Riverside County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Celery may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Celery successfully. Mulch heavily to conserve soil moisture.
Riverside County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
Drainage
Well Drained
Celery 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 Riverside County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Celery's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Riverside County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
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 Aug 06 to harvest before frost.
For a dedicated fall crop, sow by Oct 09.
Celery Water Budget
Water stress score is 10/10 — 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 | — | 3.5" | 0" | ❄️ Dormant |
| Feb | 5.6" | 3.6" | 2" | 💧 Light watering |
| Mar | 5.6" | 2.2" | 3.4" | 🚿 Regular watering |
| Apr | 5.6" | 1.2" | 4.4" | 🚿 Regular watering |
| May | 5.6" | 0.4" | 5.2" | 🚿 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" | 0.2" | 5.4" | 🚿 Regular watering |
| Oct | 5.6" | 0.6" | 5" | 🚿 Regular watering |
| Nov | 5.6" | 1.5" | 4.1" | 🚿 Regular watering |
| Dec | 5.6" | 2.4" | 3.2" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Riverside 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 — Riverside County, CA
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 27 | Jan 27 – Feb 10 |
| Transplant Outdoors | February 24 | Feb 24 – Mar 10 |
| Direct Sow | February 3 | Feb 3 – Feb 24 |
| Harvest | May 19 | May 19 – Jul 14 |
| Fall Sowing | October 9 | Oct 9 – Oct 23 |
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 10a
📆 Growing Season
283 days in Riverside County
Growing Tips for Celery in Riverside County
Direct sow Celery outdoors after February 24 in Riverside County when soil has warmed and frost danger has passed.
With summer highs reaching 102°F in Riverside County, provide afternoon shade for Celery and water deeply in the morning.
Common pests for Celery in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
Riverside County receives only 16" 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 Riverside County, CA?
Riverside County is in Zone 10a with an average last frost of February 24. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Riverside County, CA?
Riverside County, California is in USDA Hardiness Zone 10a. The average last spring frost is February 24 and first fall frost is December 4.
When should I plant Celery in Riverside County, CA?
In Riverside County, CA, plant Celery after the last frost (around February 24) and before the first frost (around December 4). Best results when soil holds above 50°F.
What growing zone is Riverside County, CA for Celery?
Riverside County sits in USDA Zone 10a. Celery grows reliably in zones 2a through 10b, so it's a good fit here.
Can Celery grow in Riverside County's climate?
Yes — Celery grows well in Riverside County's temperate climate. Riverside County averages a 284-day frost-free season, with last frost around February 24 and first frost around December 4.
Your Riverside County Garden Planner — Free
A 22-page printable planner built for Riverside County (Zone 10a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.