Zone 6b Frost Dates & Planting Calendar

What zone 6b actually tells you

The 2023 USDA Plant Hardiness Zone Map puts a place in zone 6b when the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020. The zone says which perennials survive the winter, not when to plant in spring.

Across the 695 NOAA stations behind zone 6b ZIP pages, the median 50% last spring frost is April 23 and the median first fall frost October 21; the last frost alone ranges from March 31 to June 11 from one station to another.

Frost dates answer the planting question, and they are read from the nearest NOAA station, not from the zone. The zone 6b ZIP codes here lie in 36 states; pick your own ZIP code below, or look up the zone of any ZIP code.