When to plant Celery in Sumner, ME
For Celery in Sumner, the safe spring window opens around May 2 and closes around May 23. Last expected frost is May 16, first fall frost September 29, giving a 136-day growing season. A second sowing from July 21 to August 4 extends the harvest into fall.
When to Plant Celery in Sumner, ME
Your July gardening checklist
A quick July briefing for Oxford County, Maine gardeners — what's urgent, what's next, and what can wait.
-
Sow celery for an autumn harvest
Keep young seedlings shaded and moist in summer heat. A row of taller crops works as natural shade.
Coming up in August — start thinking about
- 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.
Sumner, Maine is in USDA Zone 5a. The average last spring frost is May 16 and the first fall frost is September 29, giving you a growing season of approximately 136 days.
At an elevation of 186 feet, Oxford County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Celery to ensure they mature before fall.
Sumner Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.4
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 Sumner
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (4.9–6.4) is more acidic than Celery prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Oxford County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Celery.
Organic Matter
Organic matter is moderate (3.8%). Annual compost additions will help Celery.
How to Plant Celery
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Celery 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 | — | 2.7" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | — | 3.7" | 0" | ❄️ Dormant |
| May | 5.6" | 3.8" | 1.8" | 💧 Light watering |
| Jun | 5.6" | 3.6" | 2" | 💧 Light watering |
| Jul | 5.6" | 3.7" | 1.9" | 💧 Light watering |
| Aug | 5.6" | 3.6" | 2" | 💧 Light watering |
| Sep | 5.6" | 3.3" | 2.3" | 💧 Light watering |
| Oct | — | 2.8" | 0" | ❄️ Dormant |
| Nov | — | 3.4" | 0" | ❄️ Dormant |
| Dec | — | 3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Oxford 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 — Sumner, ME
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 11 | Apr 11 – Apr 25 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 2 | May 2 – May 23 |
| Harvest | August 8 | Aug 8 – Oct 3 |
| Fall Sowing | July 21 | Jul 21 – Aug 4 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.3"/week · Natural rainfall sufficient
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 5a
📆 Growing Season
136 days in Oxford County
Growing Tips for Celery in Sumner
Direct sow Celery outdoors after May 16 in Oxford 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
When should I plant Celery in Sumner, ME?
In Sumner, ME, plant Celery after the last frost (around May 16) and before the first frost (around September 29). Best results when soil holds above 50°F.
What growing zone is Sumner, ME for Celery?
Sumner sits in USDA Zone 5a. Celery grows reliably in zones 2a through 10b, so it's a good fit here.
Can Celery grow in Sumner's climate?
Yes — Celery grows well in Sumner's temperate climate. Sumner averages a 136-day frost-free season, with last frost around May 16 and first frost around September 29.
Your Oxford County Garden Planner — Free
A 22-page printable planner built for Oxford County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.