When to Plant Sweet Corn in Madison County, IN
What to do in May
May is a pivotal month for Madison County, Indiana gardens. Focus on these tasks first and you'll set up the rest of the season for success.
Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.
Madison County, Indiana is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 17, giving you a growing season of approximately 177 days.
At an elevation of 901 feet, Madison County receives approximately 32.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Sweet Corn during the growing season.
Madison County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
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 Madison County
How your county's soil matches Sweet Corn's growing requirements.
Soil pH
Your soil pH (6.0–7.2) overlaps with Sweet Corn's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Madison County is excellent for Sweet Corn — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Sweet Corn will thrive.
How to Plant Sweet Corn
Succession Planting Sweet Corn
Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sweet Corn
Sweet Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Sweet Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.5" | 3" | 💧 Light watering |
| May | 6.5" | 4" | 2.5" | 💧 Light watering |
| Jun | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| Jul | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| Aug | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Sep | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Oct | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Madison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sweet Corn 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.
Sweet Corn Planting Timeline — Madison County, IN
Sweet Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | July 2 | Jul 2 – Aug 13 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
177 days in Madison County
Growing Tips for Sweet Corn in Madison County
Direct sow Sweet Corn outdoors after April 23 in Madison County when soil has warmed and frost danger has passed.
Common pests for Sweet Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sweet Corn in Other Locations
Frequently Asked Questions
When should I plant Sweet Corn in Madison County, IN?
Madison County is in Zone 6a with an average last frost of April 23. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, IN?
Madison County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 17.
Your Madison County Garden Planner — Free
A 24-page printable planner built for Madison 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.