When to Plant Corn in Hamlin County, SD
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.
Hamlin County, South Dakota is in USDA Zone 4a. The average last spring frost is May 6 and the first fall frost is October 3, giving you a growing season of approximately 150 days.
At an elevation of 729 feet, Hamlin County receives approximately 24.8 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Corn to ensure they mature before fall.
Hamlin County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.7
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 Hamlin County
How your county's soil matches Corn's growing requirements.
Soil pH
Your soil pH (6.7–7.7) is more alkaline than Corn prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Hamlin County is excellent for Corn — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Corn.
Organic Matter
Organic matter is moderate (3.5%). Annual compost additions will help Corn.
How to Plant Corn
Succession Planting Corn
Sow every 6.9 weeks. Last sowing by Jun 25 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Corn Planting Timeline — Hamlin County, SD
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 20 | May 20 – Jun 10 |
| Harvest | July 22 | Jul 22 – Sep 16 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Direct Sow |
| June | Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4a
📆 Growing Season
150 days in Hamlin County
Growing Tips for Corn in Hamlin County
Direct sow Corn outdoors after May 06 in Hamlin County when soil has warmed and frost danger has passed.
Common pests for Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
Hamlin County receives only 25" of rain annually. Corn needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
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
Level Up Your Garden
Corn in Other Locations
Frequently Asked Questions
When should I plant Corn in Hamlin County, SD?
Hamlin County is in Zone 4a with an average last frost of May 6. Plan your Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hamlin County, SD?
Hamlin County, South Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 6 and first fall frost is October 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Hamlin County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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