When to Plant Mustard Greens in Oakland County, MI
Your May gardening checklist
Welcome to May in Zone 6a. These are the moves that will have the biggest impact on your growing season.
To set up a strong June, finish these tasks
- 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.
Oakland County, Michigan is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 20, giving you a growing season of approximately 175 days.
At an elevation of 1,286 feet, Oakland County receives approximately 39.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Mustard Greens during the growing season.
Oakland County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.1
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 Oakland County
How your county's soil matches Mustard Greens's growing requirements.
Soil pH
Your soil pH (5.9–7.1) overlaps with Mustard Greens's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Oakland County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.0%) — Mustard Greens will thrive.
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 31 to harvest before frost.
For a dedicated fall crop, sow by Aug 11.
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 5.5" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.4" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Oakland 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 — Oakland County, MI
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 24 | Mar 24 – Apr 7 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 14 | Apr 14 – May 5 |
| Harvest | June 2 | Jun 2 – Aug 4 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | 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: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
175 days in Oakland County
Growing Tips for Mustard Greens in Oakland County
Direct sow Mustard Greens outdoors after April 28 in Oakland County when soil has warmed and frost danger has passed.
Your generous 175.0-day season in Oakland 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 Oakland County, MI?
Oakland County is in Zone 6a with an average last frost of April 28. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Oakland County, MI?
Oakland County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 28 and first fall frost is October 20.
Your Oakland County Garden Planner — Free
A 24-page printable planner built for Oakland County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.