USDA Zone 4a Planting Calendar: What to Plant and When

Zone 4a means an average lowest winter temperature of -30 to -25 degrees Fahrenheit (-34 to -32 Celsius).

Your growing region in zone 4a

Zone 4a runs through the regions below. Each one has a month by month sowing calendar built on its own frost dates and summer heat, not on the zone number.

What to plant now in zone 4a: October 2026, region by region

Zone 4a runs through Upper Midwest & Northern Plains and Alaska, and each of them plants on its own calendar. These are the vegetables to sow or plant this month in each region, from the same data as the region calendars; follow the links for herbs, fruit and the full year.

Zone 4a planting calendar: what to plant each month

Zone 4a covers 2 of our regions: Upper Midwest & Northern Plains and Alaska. A zone shares a winter low, not a planting calendar, so this calendar follows each region's own sowing windows from our data. For each month, the second column lists the vegetables that every region in zone 4a can sow or plant, and the region columns give the number of vegetables each region can sow, linked to that region's month page with the full list. Each month name links to the national page for that month.

Zone 4a planting dates by crop

The first and last months to sow or plant 36 popular vegetables, herbs and fruit in each region of zone 4a. A range such as Feb to Apr means you can sow from February through April, and two ranges mean a spring and a fall window. Where our data has a crop set out as transplants, the months are transplanting months. Each crop links to its plant page, which shows the calendar for any region.

Frost dates in zone 4a

Frost dates, not the zone number, set the sowing windows above. These are the regional frost windows from our frost table, with the ZIP code records for a few places in each region. ZIP code figures come from the nearest weather station in the NOAA 1991 to 2020 Climate Normals at the 50 percent level, so in one year out of two the last frost comes later. Check your own ZIP code in the Frost Lookup.

What zone 4a is good for

Any perennial, shrub or fruit tree rated to zone 4a or lower should survive a normal winter where you are. That is the question a zone answers well. For fruit trees there is a second number that matters just as much: winter chill hours, which decide whether a variety will set fruit at all. The free app checks both.

Find your dates

Match your zip code to a region, then check the frost dates table for your sowing window.

Questions about zone 4a

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