When to Plant Collard Greens in Baltimore County, MD
This month in Baltimore County, Maryland
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Baltimore County, Maryland.
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Start collard greens under lights
You're about 26 weeks out from your last frost — the perfect window to get these germinating indoors.
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Bring in the collard greens
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Get ahead of June
- 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.
Baltimore County, Maryland is in USDA Zone 7b. The average last spring frost is April 3 and the first fall frost is November 6, giving you a growing season of approximately 217 days.
At an elevation of 641 feet, Baltimore County receives approximately 49.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Collard Greens during the growing season.
Baltimore County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7
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 Baltimore County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (5.7–7.0) overlaps with Collard Greens's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Baltimore County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Collard Greens.
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 Aug 23 to harvest before frost.
For a dedicated fall crop, sow by Aug 28.
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 | — | 3.9" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | — | 3.8" | 0" | ❄️ Dormant |
| Apr | 3.5" | 3.7" | 0" | ✅ Rainfall sufficient |
| May | 3.5" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 5.5" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 4.2" | 0" | ✅ Rainfall sufficient |
| Oct | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | 3.5" | 3.8" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Baltimore 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 — Baltimore County, MD
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 27 | Feb 27 – Mar 13 |
| Transplant Outdoors | April 3 | Apr 3 – Apr 17 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Harvest | May 29 | May 29 – Jul 31 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| 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 7b
📆 Growing Season
217 days in Baltimore County
Growing Tips for Collard Greens in Baltimore County
Direct sow Collard Greens outdoors after April 03 in Baltimore 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 Baltimore County, MD?
Baltimore County is in Zone 7b with an average last frost of April 3. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Baltimore County, MD?
Baltimore County, Maryland is in USDA Hardiness Zone 7b. The average last spring frost is April 3 and first fall frost is November 6.
Your Baltimore County Garden Planner — Free
A 24-page printable planner built for Baltimore County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.