Free planting guide · PDF
Zone 4b planting guide
A one-page zone 4b planting guide: average last and first frost dates, what vegetables to plant when in spring and fall, and how to pick perennials for zone 4b.
What is on this planting guide
Average coldest winter night -25 to -20°F (-32 to -29°C). Places in zone 4b include Duluth, MN, Saint Cloud, MN, Helena, MT, Montpelier, VT.
Spring: what to plant and when
| Group | Plant outside | Crops |
|---|---|---|
| Hardy crops tolerate a hard frost | March 27 to April 10 | Asparagus, broccoli, Brussels sprouts, cabbage, collards, horseradish, kale, kohlrabi, leek, mustard, onion, peas, potato, radish, rhubarb, spinach, turnip |
| Semi-hardy crops tolerate a light frost | April 10 to April 24 | Beet, carrot, cauliflower, celery, chard, Chinese cabbage, lettuce, mustard, parsnip |
| Tender crops damaged by frost | From May 8 | Bean, sweet corn, tomato |
| Very tender crops warm season | From May 22 | Cucumber, eggplant, melons, okra, pepper, pumpkin, squash, sweet potato |
Fall garden
Count back from the first fall frost (October 1): days to harvest, plus about 14 days because growth slows in fall, plus 14 more for frost-tender crops. A 50-day crop goes in by July 29 , a 70-day crop by July 9 .
| Semi-hardy (take light frost) | Beets, mustard, radishes, spinach, Swiss chard, green onions |
| Hardy (take several frosts) | Cabbage, carrots, turnips, rutabagas, kale |
Frost dates: medians across 1,270 zone 4b ZIP codes, from the nearest NOAA 1991-2020 climate normals station (32°F, 50% chance). Spring timing: Purdue Extension HO-186-W. Fall method and crops: University of Nebraska-Lincoln Extension NebGuide G1343. Your own dates by ZIP code: plantsdirectusa.com.
