When to Plant Peppers in Boone County, IL
Sweet peppers are warm-season crops producing fruits in a rainbow of colors. They turn from green to red, yellow, or orange as they ripen, increasing in sweetness.
Boone County, Illinois is in USDA Zone 5a. The average last spring frost is April 23 and the first fall frost is October 16, giving you a growing season of approximately 176 days.
At an elevation of 512 feet, Boone County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Peppers to ensure they mature before fall.
Boone County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
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.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Peppers Planting Timeline — Boone County, IL
Peppers Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 12 | Feb 12 – Feb 26 |
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | July 9 | Jul 9 – Sep 17 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–90 days
Soil pH
6 – 7
USDA Zone
Zone 5a
Growing Season
176 days
Growing Tips for Boone County
Start seeds indoors 8-10 weeks before last frost. Transplant when nighttime temperatures stay above 55F. Avoid high-nitrogen fertilizers which promote leaves over fruit.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Isolate 300 ft for purity. Hot and sweet peppers can cross-pollinate.
Peppers in Other Locations
Frequently Asked Questions
When should I plant Peppers in Boone County, IL?
Boone County is in Zone 5a with an average last frost of April 23. Plan your Peppers planting based on this frost date — see the calendar above for exact timing.
What planting zone is Boone County, IL?
Boone County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 23 and first fall frost is October 16.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Boone County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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