When to plant Corn in St. Joseph County, MI
In Zone 6a (St. Joseph County), direct-sow Corn between May 5 and May 26 for spring, after the April 28 last-frost mark.
When to Plant Corn in St. Joseph County, MI
Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.
St. Joseph County, Michigan is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 16, giving you a growing season of approximately 171 days.
At an elevation of 564 feet, St. Joseph County receives approximately 39.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Corn to ensure they mature before fall.
St. Joseph County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.7
Drainage
Well Drained
How Much Corn to Grow
For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In St. Joseph County's 171-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Corn
Corn needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Oct | 4.3" | 3" | 1.3" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Joseph County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Corn Planting Timeline — St. Joseph County, MI
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 5 | May 5 – May 26 |
| Harvest | July 7 | Jul 7 – Sep 1 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | 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
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
171 days in St. Joseph County
Growing Tips for St. Joseph County
Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Corn in Other Locations
Frequently Asked Questions
When should I plant Corn in St. Joseph County, MI?
St. Joseph County is in Zone 6a with an average last frost of April 28. Plan your Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Joseph County, MI?
St. Joseph County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 28 and first fall frost is October 16.
When should I plant Corn in St. Joseph County, MI?
In St. Joseph County, MI, plant Corn after the last frost (around April 28) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is St. Joseph County, MI for Corn?
St. Joseph County sits in USDA Zone 6a. Corn grows reliably in zones 3a through 11b, so it's a good fit here.
Can Corn grow in St. Joseph County's climate?
Yes — Corn grows well in St. Joseph County's temperate climate. St. Joseph County averages a 171-day frost-free season, with last frost around April 28 and first frost around October 16.
Your St. Joseph County Garden Planner — Free
A 22-page printable planner built for St. Joseph County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.