When to Plant Mint in St. Francois County, MO
May in St. Francois County, Missouri — your action list
Your St. Francois County, Missouri garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
Looking ahead to June
- First harvests: mint
Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.
St. Francois County, Missouri is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.
At an elevation of 808 feet, St. Francois County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Mint during the growing season.
St. Francois County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-7
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 St. Francois County
How your county's soil matches Mint's growing requirements.
Soil pH
Your soil pH (5.3–7.0) overlaps with Mint's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in St. Francois County is excellent for Mint — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Mint.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Mint.
How to Plant Mint
Succession Planting Mint
Sow every 6.9 weeks. Last sowing by Jul 23 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Mint
Mint needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Mint Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 3" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.1" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Francois County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Mint 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.
Mint Planting Timeline — St. Francois County, MO
Mint Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Harvest | June 25 | Jun 25 – Sep 3 |
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
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
188 days in St. Francois County
Growing Tips for Mint in St. Francois County
Direct sow Mint outdoors after April 16 in St. Francois County when soil has warmed and frost danger has passed.
General growing tips
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 St. Francois County, MO?
St. Francois County is in Zone 6b with an average last frost of April 16. Plan your Mint planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Francois County, MO?
St. Francois County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 21.
Your St. Francois County Garden Planner — Free
A 24-page printable planner built for St. Francois 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.