Gardening in zone 4b
In USDA zone 4b, the coldest winter night averages -25 to -20°F. The typical last spring frost is around May 8 and the first fall frost around Oct 1.
A zone tells you about winter cold, not about timing: across zone 4b, last spring frosts range from about May 1 to May 26, and first fall frosts from Sep 18 to Oct 8. Plan from your own frost dates where you can.
Zone 4b is common in: Minnesota, Wisconsin, South Dakota, Montana, New York, Vermont, Wyoming, Michigan, North Dakota, Maine, Iowa
Zone 4b planting schedule
Dates below count from the zone’s typical frost dates, so treat them as a starting point. For dates set to your exact ZIP code, use the planting calendar.
| Crop | Start indoors | Plant or sow outside | Fall planting |
|---|---|---|---|
| Tomato | Around Mar 27 | Around May 22 | — |
| Pepper | Around Mar 13 | Around May 22 | — |
| Eggplant | Around Mar 13 | Around May 22 | — |
| Basil | Around Mar 27 | Around May 22 | — |
| Cucumber | Around Apr 17 | Around May 22 | — |
| Zucchini | Around Apr 17 | Around May 15 | — |
| Butternut Squash | Around Apr 17 | Around May 15 | — |
| Watermelon | Around Apr 17 | Around May 22 | — |
| Corn | — | Around May 8 | — |
| Green Bean | — | Around May 15 | — |
| Pea | — | Around Mar 27 | Around Jul 23 |
| Lettuce | — | Around Apr 10 | Around Aug 13 |
| Spinach | — | Around Mar 27 | Around Aug 6 |
| Kale | Around Mar 27 | Around May 8 | Around Jul 23 |
| Broccoli | Around Mar 13 | Around Apr 24 | Around Jun 25 |
| Cabbage | Around Mar 27 | Around May 8 | Around Jun 25 |
| Carrot | — | Around Apr 17 | Around Jul 16 |
| Beet | — | Around Apr 10 | Around Jul 23 |
| Radish | — | Around Apr 10 | Around Aug 20 |
| Onion | Around Feb 27 | Around Apr 17 | — |
| Potato | — | Around Apr 24 | — |
| Garlic | — | — | Around Oct 15 |
Zones: 2023 USDA Plant Hardiness Zone Map. Frost dates: NOAA NCEI U.S. Climate Normals 1991–2020 (50% chance of 32°F), middle value across the zone's ZIP codes.
Other zones: 3b · 4a · 5a · 5b · 6a · 6b · 7a · 7b · 8a · 8b · 9a · 9b · 10a