Free planting guide · PDF
Zone 4a planting guide
A one-page zone 4a planting guide: average last and first frost dates, what vegetables to plant when in spring and fall, and how to pick perennials for zone 4a.
What is on this planting guide
Average coldest winter night -30 to -25°F (-34 to -32°C). Places in zone 4a include Fargo, ND, Bismarck, ND, Grand Forks, ND.
Spring: what to plant and when
| Group | Plant outside | Crops |
|---|---|---|
| Hardy crops tolerate a hard frost | March 31 to April 14 | 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 14 to April 28 | Beet, carrot, cauliflower, celery, chard, Chinese cabbage, lettuce, mustard, parsnip |
| Tender crops damaged by frost | From May 12 | Bean, sweet corn, tomato |
| Very tender crops warm season | From May 26 | Cucumber, eggplant, melons, okra, pepper, pumpkin, squash, sweet potato |
Fall garden
Count back from the first fall frost (September 28): 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 26 , a 70-day crop by July 6 .
| 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 792 zone 4a 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.
