When to Plant Spinach in Oxford County, ME
Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.
Oxford County, Maine is in USDA Zone 4b. 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 Spinach to ensure they mature before fall.
Oxford County Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.4
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 Oxford County
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (4.9–6.4) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Oxford County is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Spinach.
Organic Matter
Organic matter is moderate (3.8%). Annual compost additions will help Spinach.
How to Plant Spinach
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Spinach
Sow every 4 weeks. Last sowing by Aug 10 to harvest before frost.
For a dedicated fall crop, sow by Jul 07.
Plant Water Budget
Monthly Watering Guide for Spinach
Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Spinach 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 | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| 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.
Spinach 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.
Spinach Planting Timeline — Oxford County, ME
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 4 | Apr 4 – Apr 18 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 9 | May 9 – May 30 |
| Harvest | June 20 | Jun 20 – Aug 22 |
| Fall Sowing | July 7 | Jul 7 – Jul 21 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 4b
📆 Growing Season
136 days in Oxford County
Growing Tips for Spinach in Oxford County
Direct sow Spinach outdoors after May 16 in Oxford County when soil has warmed and frost danger has passed.
Your generous 136.0-day season in Oxford County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.
General growing tips
Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.
Spinach in Other Locations
Frequently Asked Questions
When should I plant Spinach in Oxford County, ME?
Oxford County is in Zone 4b with an average last frost of May 16. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Oxford County, ME?
Oxford County, Maine is in USDA Hardiness Zone 4b. The average last spring frost is May 16 and first fall frost is September 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Oxford County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.
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