Planting Calendar & Monthly Lists
Scroll to Map & Zone DescriptionNOTE: No Planting in Winter Months.
Extreme Minimum Temperate −37.2 to −34.4°C (−35 to −30°F)
Continental Subarctic and Alpine Climates - Short Mild Humid Summers and Extremely Cold winters
Indicative Towns: Tomahawk, Wisconsin; Sidney, Montana
Zone 3b areas typically have a humid continental climate (Köppen: Dfb), with long, extremely cold winters and humid warm summers
Plant hardiness Zone 3 (a & a) is found throughout Alaska, and in high altitude areas in northern United States. Zone 3 (a & a) features minimum average temperatures of -40 to -30 degrees F. Depending on your location growing conditions can also be affected by high winds, extreme cold and low rainfall in summer.
Zone 3 (a & b) has a very short growing season for growing vegetables and herbs. The last frost date is around the middle of May. The first frost date is generally in mid-September. Adding row covers can help extend the growing season and warm the ground. Plant vegetables that germinate and mature quickly to beat early frosts. In addition to Zone 2 plants, vegetables to plant in summer include: Cucumbers, Summer squash, Asparagus, Winter squash and Celery. Some additional herbs to plant include: English chamomile, French sorrel, Caraway, Catnip, Horseradish, Peppermint, Parsley and Garlic.
Towns Include:
Bemidji, Minnesota
Grand Rapids, Minnesota
Tomahawk, Wisconsin
Turtle River, Minnesota
Wolf Point, Montana