When to Plant Collard Greens in Cimarron County, OK
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.
Cimarron County, Oklahoma is in USDA Zone 6b. The average last spring frost is April 19 and the first fall frost is October 18, giving you a growing season of approximately 182 days.
At an elevation of 1,132 feet, Cimarron County receives approximately 28.5 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Collard Greens during the growing season.
Cimarron County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.4
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 Cimarron County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (6.5–7.4) overlaps with Collard Greens's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Cimarron County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Collard Greens.
Organic Matter
Organic matter is moderate (3.5%). 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 04 to harvest before frost.
For a dedicated fall crop, sow by Aug 09.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | 3.5" | 2.7" | 0.8" | 💧 Light watering |
| May | 3.5" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 2.9" | 0.6" | 💧 Light watering |
| Sep | 3.5" | 2.3" | 1.2" | 💧 Light watering |
| Oct | 3.5" | 1.9" | 1.6" | 💧 Light watering |
| Nov | — | 0.9" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cimarron 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 — Cimarron County, OK
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | April 19 | Apr 19 – May 3 |
| Direct Sow | April 5 | Apr 5 – Apr 26 |
| Harvest | June 14 | Jun 14 – Aug 16 |
| Fall Sowing | August 9 | Aug 9 – Aug 23 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · 1-2 times/week
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
182 days in Cimarron County
Growing Tips for Collard Greens in Cimarron County
Direct sow Collard Greens outdoors after April 19 in Cimarron 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
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Collard Greens in Other Locations
Frequently Asked Questions
When should I plant Collard Greens in Cimarron County, OK?
Cimarron County is in Zone 6b with an average last frost of April 19. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cimarron County, OK?
Cimarron County, Oklahoma is in USDA Hardiness Zone 6b. The average last spring frost is April 19 and first fall frost is October 18.
Plan Your Garden with Confidence
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