Plant Beets in Zone 5b

Zone 5b averages 166 frost-free days, running from a last spring frost around April 25 to a first fall frost around October 8. Beets needs roughly 55 days from planting out to first harvest, so it uses about 33 percent of that window. Beets is a hardy crop, which is what decides where in the window it belongs.

Beets handles cold soil, so there is no reason to wait for the frost date. Direct sow around Apr 4, roughly 3 weeks before the Zone 5b last frost, as soon as the ground is workable. Sowing at the last frost instead costs you the coolest and best part of the season. At 55 days to harvest, a 166-day Zone 5b season has room for about 2 sowings, so stagger them rather than planting everything at once.

Yes. Sow beets by August 21 in Zone 5b. That is 48 days before the average first frost, which covers the 55 days to maturity plus about two weeks for the slower growth that comes with shortening days, minus the roughly 21 days beets keeps going once light frost arrives.

Beets sown for fall give you two crops at once: greens within a month and roots that sweeten in cold soil.