Zone 4a planting calendar
What to plant in January — 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
Plan & order
- Inventory and order seedaround Jan 28
Sort what you already have, toss anything over 3 years old, and order early while varieties are in stock.
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