Zone 1a planting calendar

What to plant in September: zone 1a

Zone 1a averages its last spring frost around June 20 and its first fall frost around August 10. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.

These are zone-average dates. Check an area-level frost estimate from thirty years of nearby weather history and this calendar retimes itself.

Last frost: June 20

First frost: August 10

Winter lows: -60 to -55 °F

Zone 1a Almanac. What growers here actually recorded: sowing weeks, days to first pick, and yields.

A quiet month in zone 1a

September 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 October.

Turn this into your own calendar

Want this calendar emailed to you?

Get the full 12-month version for your ZIP area. Every sowing, transplant, and harvest window, with reminders you can add to your calendar.

Build my free plan Find my zone & frost dates