When to Plant Radish in Dewey County, SD
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Dewey County, South Dakota is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is October 3, giving you a growing season of approximately 145 days.
At an elevation of 1,004 feet, Dewey County receives approximately 25.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Radish to ensure they mature before fall.
Dewey County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.6
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
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Radish Planting Timeline — Dewey County, SD
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 4 | May 4 – May 25 |
| Fall Sowing | July 11 | Jul 11 – Jul 25 |
| Harvest | June 1 | Jun 1 – Jun 22 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Direct Sow |
| June | Harvest |
| July | Fall Sowing |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
22–35 days
Soil pH
6 – 7
USDA Zone
Zone 4a
Growing Season
145 days
Growing Tips for Dewey County
Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Dewey County, SD?
Dewey County is in Zone 4a with an average last frost of May 11. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Dewey County, SD?
Dewey County, South Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is October 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Dewey County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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