Zone 4a planting calendar
What to plant in October — zone 4a
Zone 4a averages its last spring frost around May 20 and its first fall frost around September 20. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.
Last frost: May 20
First frost: September 20
Winter lows: -30 to -25 °F
A quiet month in zone 4a
October is a rest-and-plan month here. Use it to order seed, test your soil, repair beds, and map next season's rotation — then jump ahead to November.
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