When to Plant Celery in Coos County, OR
Your May planting checklist for Coos County, Oregon
A quick May briefing for Coos County, Oregon gardeners — what's urgent, what's next, and what can wait.
A few tasks this May that'll pay off in June
- 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.
Coos County, Oregon is in USDA Zone 9a. The average last spring frost is March 22 and the first fall frost is November 19, giving you a growing season of approximately 242 days.
At an elevation of 96 feet, Coos County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Celery during the growing season.
Coos County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.8
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 Coos County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (5.4–6.8) overlaps with Celery's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Coos County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.7%) — Celery will thrive.
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 22 to harvest before frost.
For a dedicated fall crop, sow by Sep 24.
Plant Water Budget
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 | — | 5.5" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 5.6" | 4.4" | 1.2" | 💧 Light watering |
| Apr | 5.6" | 3.1" | 2.5" | 💧 Light watering |
| May | 5.6" | 2.3" | 3.3" | 🚿 Regular watering |
| Jun | 5.6" | 1.6" | 4" | 🚿 Regular watering |
| Jul | 5.6" | 0.6" | 5" | 🚿 Regular watering |
| Aug | 5.6" | 0.8" | 4.8" | 🚿 Regular watering |
| Sep | 5.6" | 1.4" | 4.2" | 🚿 Regular watering |
| Oct | 5.6" | 3.3" | 2.3" | 💧 Light watering |
| Nov | 5.6" | 5.9" | 0" | ✅ Rainfall sufficient |
| Dec | — | 5.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Coos 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 — Coos County, OR
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 22 | Feb 22 – Mar 8 |
| Transplant Outdoors | March 22 | Mar 22 – Apr 5 |
| Direct Sow | March 1 | Mar 1 – Mar 22 |
| Harvest | June 14 | Jun 14 – Aug 9 |
| Fall Sowing | September 24 | Sep 24 – Oct 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.3"/week · 1-2 times/week
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
242 days in Coos County
Growing Tips for Celery in Coos County
Direct sow Celery outdoors after March 22 in Coos 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 Coos County, OR?
Coos County is in Zone 9a with an average last frost of March 22. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Coos County, OR?
Coos County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is March 22 and first fall frost is November 19.
Your Coos County Garden Planner — Free
A 24-page printable planner built for Coos County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.