Zone 3b planting calendar

What to plant in September: zone 3b

A rule-of-thumb starting point for zone 3b: last spring frost around May 25, first fall frost around September 15. Zones are set by winter lows, not frost dates, so two gardens in the same zone can be weeks apart. Measure your ZIP below for dates from your area's own 30-year record.

These are zone-average dates. Check an area-level frost estimate from thirty years of nearby weather history and this calendar retimes itself.
Typical last frost: May 25
Typical first frost: September 15
Winter lows: -35 to -30 °F
Zone 3b Almanac. What growers here actually recorded: sowing weeks, days to first pick, and yields.

Plant to overwinter

  • Garlicaround Sep 1

    Cloves go in about two weeks before first frost. They root now, sleep, then bulb next summer.

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