When to plant Mint in Grundy County, IL
In Grundy County, Mint is a single-season spring crop — there's no second fall window. Plant April 27–May 11 for an 60–90-day harvest, finishing well before the October 17 first frost.
When to Plant Mint in Grundy County, IL
Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.
Grundy County, Illinois is in USDA Zone 5b. The average last spring frost is April 20 and the first fall frost is October 17, giving you a growing season of approximately 180 days.
At an elevation of 629 feet, Grundy County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Mint during the growing season.
Grundy County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Mint Planting Timeline — Grundy County, IL
Mint Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Harvest | June 29 | Jun 29 – Sep 7 |
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 | Harvest |
| 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
180 days in Grundy County
Growing Tips for Grundy 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
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Mint in Other Locations
Frequently Asked Questions
When should I plant Mint in Grundy County, IL?
Grundy County is in Zone 5b with an average last frost of April 20. Plan your Mint planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grundy County, IL?
Grundy County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 20 and first fall frost is October 17.
When should I plant Mint in Grundy County, IL?
In Grundy County, IL, plant Mint after the last frost (around April 20) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Grundy County, IL for Mint?
Grundy 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 Grundy County's climate?
Yes — Mint grows well in Grundy County's temperate climate. Grundy County averages a 180-day frost-free season, with last frost around April 20 and first frost around October 17.
Your Grundy County Garden Planner — Free
A 22-page printable planner built for Grundy 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.