When to Plant Onions in Minnesota
In Minnesota, the time to plant onions outside runs from Mar 26 – Apr 9 in Minneapolis to Apr 16 – Apr 30 in Duluth. In Minneapolis, it's Mar 26 – Apr 9. The average last spring frost differs by about 3 weeks across the state (Apr 23 in Minneapolis, May 14 in Duluth), so use the dates for the town nearest you.
Onions are cold-hardy. Plant sets or transplants early so they grow leaves before long summer days trigger bulbing.
- Start indoors: 10–12 weeks before the last frost.
- Plant outside: 2–4 weeks before the last frost.
Onions planting dates in Minnesota by city
| City | Zone | Start indoors | Plant outside |
|---|---|---|---|
| Andover | 4b | Feb 10 – Feb 24 | Apr 7 – Apr 21 |
| Apple Valley | 5a | Feb 7 – Feb 21 | Apr 4 – Apr 18 |
| Austin | 4b | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Blaine | 5a | Feb 10 – Feb 24 | Apr 7 – Apr 21 |
| Bloomington | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Brooklyn Center | 5a | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Brooklyn Park | 5a | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Burnsville | 5a | Feb 2 – Feb 16 | Mar 30 – Apr 13 |
| Chaska | 4b | Feb 10 – Feb 24 | Apr 7 – Apr 21 |
| Coon Rapids | 5a | Feb 10 – Feb 24 | Apr 7 – Apr 21 |
| Cottage Grove | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Duluth | 4b | Feb 19 – Mar 5 | Apr 16 – Apr 30 |
| Eagan | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Eden Prairie | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Edina | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Elk River | 4b | Feb 9 – Feb 23 | Apr 6 – Apr 20 |
| Fridley | 5a | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Inver Grove Heights | 5a | Jan 30 – Feb 13 | Mar 27 – Apr 10 |
| Lakeville | 4b | Feb 2 – Feb 16 | Mar 30 – Apr 13 |
| Mankato | 5a | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Maple Grove | 5a | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Maplewood | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Minneapolis | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Minnetonka | 5a | Feb 4 – Feb 18 | Apr 1 – Apr 15 |
| Moorhead | 4a | Feb 10 – Feb 24 | Apr 7 – Apr 21 |
| Oakdale | 5a | Feb 1 – Feb 15 | Mar 29 – Apr 12 |
| Plymouth | 5a | Feb 4 – Feb 18 | Apr 1 – Apr 15 |
| Prior Lake | 4b | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Ramsey | 4b | Feb 9 – Feb 23 | Apr 6 – Apr 20 |
| Richfield | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Rochester | 4b | Feb 5 – Feb 19 | Apr 2 – Apr 16 |
| Rosemount | 5a | Feb 7 – Feb 21 | Apr 4 – Apr 18 |
| Roseville | 5a | Feb 3 – Feb 17 | Mar 31 – Apr 14 |
| Savage | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Shakopee | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| Shoreview | 5a | Jan 29 – Feb 12 | Mar 26 – Apr 9 |
| St. Cloud | 4b | Feb 12 – Feb 26 | Apr 9 – Apr 23 |
| St. Louis Park | 5a | Feb 4 – Feb 18 | Apr 1 – Apr 15 |
| St. Paul | 5a | Jan 30 – Feb 13 | Mar 27 – Apr 10 |
| Woodbury | 5a | Feb 1 – Feb 15 | Mar 29 – Apr 12 |
Calculated from each town's average (50%) frost dates, from the nearest NOAA station (1991–2020). Typical dates for the 2027 planting season, based on NOAA's 1991–2020 averages. They are long-term odds, not a forecast: always check your local forecast before planting. Zones: 2023 USDA Plant Hardiness Zone Map (USDA-ARS and Oregon State University). Not the official map; see planthardiness.ars.usda.gov.
See all frost dates in Minnesota, or the general guide to when to plant onions.
Getting beds ready? Work out how much raised bed soil, compost or mulch you need with our sister site, Yard Coverage.