When to Plant Radishes in Minnesota
The fastest vegetable in the garden — some varieties are ready in just 25 days. Perfect for impatient gardeners and kids.
The Short Answer
Minnesota Frost Dates
Your planting dates depend on which part of Minnesota you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Minnesota | 3a, 3b | May 15 - Jun 1 | Sep 5 - Sep 20 |
| Central Minnesota | 3b, 4a | May 5 - May 20 | Sep 15 - Oct 1 |
| Southern Minnesota | 4a, 4b | Apr 25 - May 10 | Sep 25 - Oct 10 |
Radishes Planting Schedule for Minnesota
Northern Minnesota (Zones 3a, 3b)
Average last frost: May 15 - Jun 1 · Average first frost: Sep 5 - Sep 20
Central Minnesota (Zones 3b, 4a)
Average last frost: May 5 - May 20 · Average first frost: Sep 15 - Oct 1
Southern Minnesota (Zones 4a, 4b)
Average last frost: Apr 25 - May 10 · Average first frost: Sep 25 - Oct 10
Growing Radishes in Minnesota
Radishes in Minnesota's Climate
Radishes are perfect for cold-climate gardens — they're the fastest crop from seed to harvest (as few as 22 days) and tolerate frost. Direct sow as soon as soil thaws. Your cool, long spring means radishes grow for weeks without the bolting pressure that ends the season rapidly in warm zones. Fall radishes from an August sowing are equally productive.
Soil Considerations for Minnesota
Rich prairie soils in south and west. Rocky and thin soils in north. Generally excellent for gardening in southern half. Loose, well-drained soil is especially important for radishes since the edible portion grows underground. If your soil is heavy clay, consider raised beds.
Minnesota Climate & Growing Season
Long, cold winters. Warm summers. Short but productive growing season with long summer days. Hardy varieties essential. Radishes can handle frost well, which is an advantage in Minnesota's climate. You can push planting dates earlier in spring and extend into fall.
Growing season length varies across Minnesota: Northern Minnesota (3a, 3b) has a last frost around May 15 - Jun 1, while Southern Minnesota (4a, 4b) sees frost end around Apr 25 - May 10. This difference matters for radishes — but radishes handle frost well, so the timing difference is less critical.
Growing Tips
Don't let them stay in the ground too long — they get pithy and hot. Succession plant every 2 weeks for continuous harvest.
Companion Planting
Plant radishes alongside these companions for better growth:
The Bottom Line
Last reviewed: March 29, 2026