When to Plant Collard Greens in Jasper County, IL
Your May gardening checklist
A quick May briefing for Jasper County, Illinois gardeners — what's urgent, what's next, and what can wait.
-
Indoor seed-starting week for collard greens
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
Looking ahead to 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.
Jasper County, Illinois is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 20, giving you a growing season of approximately 190 days.
At an elevation of 1,384 feet, Jasper County receives approximately 35 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Collard Greens during the growing season.
Jasper County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.3
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 Jasper County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (5.9–7.3) overlaps with Collard Greens's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Jasper County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — 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 Aug 06 to harvest before frost.
For a dedicated fall crop, sow by Aug 11.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 3.5" | 3.1" | 0.4" | 💧 Light watering |
| May | 3.5" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.3" | 0.2" | 💧 Light watering |
| Aug | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 3.4" | 0.1" | 💧 Light watering |
| Oct | 3.5" | 3" | 0.5" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Jasper 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 — Jasper County, IL
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 9 | Mar 9 – Mar 23 |
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Harvest | June 8 | Jun 8 – Aug 10 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Only during dry spells
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
190 days in Jasper County
Growing Tips for Collard Greens in Jasper County
Direct sow Collard Greens outdoors after April 13 in Jasper 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 Jasper County, IL?
Jasper County is in Zone 6b with an average last frost of April 13. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jasper County, IL?
Jasper County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 20.
Your Jasper County Garden Planner — Free
A 24-page printable planner built for Jasper County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.