Zone 5a planting calendar
What to plant in September — zone 5a
Zone 5a averages its last spring frost around May 10 and its first fall frost around October 1. 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 10
First frost: October 1
Winter lows: -20 to -15 °F
Sow cover crop
- Cover crop (cereal rye + crimson clover)around Sep 1
Sown a month before frost it germinates, holds your soil all winter, and feeds it in spring.
Direct sow for fall
Plant to overwinter
- Garlicaround Sep 17
Cloves go in about two weeks before first frost — they root now, sleep, then bulb next summer.
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