When to plant Mint in Warren County, IL
Plant Mint in Warren County, between April 20 and May 4 — the only viable window. Zone 5b's short season (191 frost-free days) rules out a fall crop.
When to Plant Mint in Warren County, IL
Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.
Warren County, Illinois is in USDA Zone 5b. The average last spring frost is April 13 and the first fall frost is October 21, giving you a growing season of approximately 191 days.
At an elevation of 801 feet, Warren County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Mint during the growing season.
Warren County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Mint Planting Timeline — Warren County, IL
Mint Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Harvest | June 22 | Jun 22 – Aug 31 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
High — keep soil consistently moist
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
191 days in Warren County
Growing Tips for Warren County
Always grow mint in containers or with underground barriers to control spreading. Harvest regularly to keep plants compact. Cut plants back in late summer for a fresh fall flush.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Mint in Other Locations
Frequently Asked Questions
When should I plant Mint in Warren County, IL?
Warren County is in Zone 5b with an average last frost of April 13. Plan your Mint planting based on this frost date — see the calendar above for exact timing.
What planting zone is Warren County, IL?
Warren County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 13 and first fall frost is October 21.
When should I plant Mint in Warren County, IL?
In Warren County, IL, plant Mint after the last frost (around April 13) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Warren County, IL for Mint?
Warren County sits in USDA Zone 5b. Mint grows reliably in zones 3a through 10b, so it's a good fit here.
Can Mint grow in Warren County's climate?
Yes — Mint grows well in Warren County's temperate climate. Warren County averages a 191-day frost-free season, with last frost around April 13 and first frost around October 21.
Your Warren County Garden Planner — Free
A 22-page printable planner built for Warren County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.