When to Plant Mint in DeKalb County, MO
Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.
DeKalb County, Missouri is in USDA Zone 5b. The average last spring frost is April 14 and the first fall frost is October 18, giving you a growing season of approximately 187 days.
At an elevation of 917 feet, DeKalb County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Mint during the growing season.
DeKalb County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-7.1
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
Mint Planting Timeline — DeKalb County, MO
Mint Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Harvest | June 23 | Jun 23 – Sep 1 |
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
6 – 7
USDA Zone
Zone 5b
Growing Season
187 days
Growing Tips for DeKalb 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
Level Up Your Garden
Mint in Other Locations
Frequently Asked Questions
When should I plant Mint in DeKalb County, MO?
DeKalb County is in Zone 5b with an average last frost of April 14. Plan your Mint planting based on this frost date — see the calendar above for exact timing.
What planting zone is DeKalb County, MO?
DeKalb County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 14 and first fall frost is October 18.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help DeKalb County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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