What to plant in March — zone 3b
Zone 3b averages its last spring frost around May 25 and its first fall frost around September 15. 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 2
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 16
Alliums need 10-12 weeks under lights before they go out — the earliest sowing of the year.
- Onionaround Mar 16
10 weeks of indoor growth before your last frost (05-25). Match day-length to your latitude — long-day north of 37°, short-day south.
- Parsleyaround Mar 30
8 weeks of indoor growth before your last frost (05-25). Soak seeds 24 hrs before sowing. Cut outer stems and it comes back for years in mild zones.
- Chivesaround Mar 30
8 weeks of indoor growth before your last frost (05-25). Divide the clump every 3 years — one plant becomes six with no effort.
Dormant care
- Prune dormant fruit treesaround Mar 9
Prune apples, pears and peaches while fully dormant — open the center, remove crossing wood.
- Check season-extension geararound Mar 30
Patch row cover, cold frames and hoops now so a late freeze can't catch you unprepared.
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