When to Plant Celery in Washington County, ME
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.
Washington County, Maine is in USDA Zone 4b. The average last spring frost is May 9 and the first fall frost is October 7, giving you a growing season of approximately 151 days.
At an elevation of 1,184 feet, Washington County receives approximately 43.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Celery to ensure they mature before fall.
Washington County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.5
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 Washington County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (5.0–6.5) is more acidic than Celery prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Washington County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.7%). Annual compost additions will help Celery.
How to Plant Celery
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Celery
Sow every 9.1 weeks. Last sowing by Jun 09 to harvest before frost.
For a dedicated fall crop, sow by Jul 15.
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 | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 3" | 0" | ❄️ Dormant |
| Mar | — | 4.1" | 0" | ❄️ Dormant |
| Apr | — | 3.5" | 0" | ❄️ Dormant |
| May | 5.6" | 3.5" | 2.1" | 💧 Light watering |
| Jun | 5.6" | 4.7" | 0.9" | 💧 Light watering |
| Jul | 5.6" | 4.1" | 1.5" | 💧 Light watering |
| Aug | 5.6" | 4.1" | 1.5" | 💧 Light watering |
| Sep | 5.6" | 3.8" | 1.8" | 💧 Light watering |
| Oct | 5.6" | 3.4" | 2.2" | 💧 Light watering |
| Nov | — | 3.4" | 0" | ❄️ Dormant |
| Dec | — | 3.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Washington 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 — Washington County, ME
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Direct Sow | May 2 | May 2 – May 23 |
| Harvest | August 1 | Aug 1 – Sep 26 |
| Fall Sowing | July 15 | Jul 15 – Jul 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.3"/week · Only during dry spells
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 4b
📆 Growing Season
151 days in Washington County
Growing Tips for Celery in Washington County
Direct sow Celery outdoors after May 09 in Washington 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 Washington County, ME?
Washington County is in Zone 4b with an average last frost of May 9. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, ME?
Washington County, Maine is in USDA Hardiness Zone 4b. The average last spring frost is May 9 and first fall frost is October 7.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Washington County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.
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