What to plant in March — zone 3a
Zone 3a averages its last spring frost around May 30 and its first fall frost around September 10. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.
Start indoors
- Sow microgreens indoorsaround Mar 7
A tray on the windowsill gives you a cut of fresh greens every 10-14 days through the cold months.
- Start onions and leeks indoorsaround Mar 21
Alliums need 10-12 weeks under lights before they go out — the earliest sowing of the year.
- Onionaround Mar 21
10 weeks of indoor growth before your last frost (05-30). Match day-length to your latitude — long-day north of 37°, short-day south.
Dormant care
- Prune dormant fruit treesaround Mar 14
Prune apples, pears and peaches while fully dormant — open the center, remove crossing wood.
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