When to Plant Mustard Greens in Kennebec County, ME
Your May planting checklist for Kennebec County, Maine
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
-
Move mustard greens into the garden
Frost risk is low now in Kennebec County, Maine. If you've been covering beds overnight, you can stop.
June will be here before you know it — start on
- Starting indoors: mustard greens
- First harvests: mustard greens
Mustard greens are fast-growing brassicas with a spicy, peppery kick. They come in green, red, and purple varieties and are excellent cooked or in salads.
Kennebec County, Maine is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is October 5, giving you a growing season of approximately 148 days.
At an elevation of 1,032 feet, Kennebec County receives approximately 42.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Mustard Greens to ensure they mature before fall.
Kennebec County Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.4
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 Kennebec County
How your county's soil matches Mustard Greens's growing requirements.
Soil pH
Your soil pH (5.1–6.4) is more acidic than Mustard Greens prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Kennebec County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.5%). Annual compost additions will help Mustard Greens.
How to Plant Mustard Greens
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Mustard Greens
Sow every 3.4 weeks. Last sowing by Aug 16 to harvest before frost.
For a dedicated fall crop, sow by Jul 27.
Plant Water Budget
Monthly Watering Guide for Mustard Greens
Mustard Greens needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Mustard Greens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.3" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | — | 3.4" | 0" | ❄️ Dormant |
| May | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.1" | 0" | ❄️ Dormant |
| Dec | — | 3.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Kennebec County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Mustard Greens 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.
Mustard Greens Planting Timeline — Kennebec County, ME
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 5 | Apr 5 – Apr 19 |
| Transplant Outdoors | May 10 | May 10 – May 24 |
| Direct Sow | April 26 | Apr 26 – May 17 |
| Harvest | June 14 | Jun 14 – Aug 16 |
| Fall Sowing | July 27 | Jul 27 – Aug 10 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 5b
📆 Growing Season
148 days in Kennebec County
Growing Tips for Mustard Greens in Kennebec County
Direct sow Mustard Greens outdoors after May 10 in Kennebec County when soil has warmed and frost danger has passed.
Your generous 148.0-day season in Kennebec County allows multiple plantings of Mustard Greens. Sow every 15.0 days for continuous harvest.
Common pests for Mustard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in early spring or fall. Harvest young leaves for milder flavor. Plants bolt quickly in heat so grow as a cool-season crop or provide shade.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Mustard Greens in Other Locations
Frequently Asked Questions
When should I plant Mustard Greens in Kennebec County, ME?
Kennebec County is in Zone 5b with an average last frost of May 10. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kennebec County, ME?
Kennebec County, Maine is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is October 5.
Your Kennebec County Garden Planner — Free
A 24-page printable planner built for Kennebec County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.