When to Plant Collard Greens in Martin County, MN
May to-do list for Martin County, Minnesota
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Martin County, Minnesota.
June will be here before you know it — start on
- Starting indoors: collard greens
- First harvests: collard greens
Collard greens are a heat-tolerant member of the cabbage family with large, sturdy leaves. They are a Southern staple and one of the most nutritious leafy greens.
Martin County, Minnesota is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 8, giving you a growing season of approximately 164 days.
At an elevation of 984 feet, Martin County receives approximately 34.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Collard Greens to ensure they mature before fall.
Martin County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.9
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 Martin County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (5.9–6.9) overlaps with Collard Greens's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Martin County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.7%) — Collard Greens will thrive.
How to Plant Collard Greens
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Collard Greens
Sow every 6.3 weeks. Last sowing by Jul 25 to harvest before frost.
For a dedicated fall crop, sow by Jul 30.
Plant Water Budget
Monthly Watering Guide for Collard Greens
Collard Greens needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Collard Greens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 3.5" | 3.3" | 0.2" | 💧 Light watering |
| May | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.8" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 2.9" | 0.6" | 💧 Light watering |
| Oct | 3.5" | 2.9" | 0.6" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Martin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Collard 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.
Collard Greens Planting Timeline — Martin County, MN
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | June 22 | Jun 22 – Aug 24 |
| Fall Sowing | July 30 | Jul 30 – Aug 13 |
Plant 1" deep · 15" apart · Rows 24" 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 | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
164 days in Martin County
Growing Tips for Collard Greens in Martin County
Direct sow Collard Greens outdoors after April 27 in Martin County when soil has warmed and frost danger has passed.
Common pests for Collard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors or direct sow 4-6 weeks before last frost. Harvest lower leaves first, leaving the growing tip intact. Flavor improves after exposure to frost.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Collard Greens in Other Locations
Frequently Asked Questions
When should I plant Collard Greens in Martin County, MN?
Martin County is in Zone 5a with an average last frost of April 27. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Martin County, MN?
Martin County, Minnesota is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 8.
Your Martin County Garden Planner — Free
A 24-page printable planner built for Martin 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.