When to plant potatoes in zone 7b

The zone 7b schedule for potatoes

Sow outdoors

March 25 to April 1

Soil warm enough (50°F), about

March 25

First harvest, roughly

June 18 to July 30

Plant for a fall crop

July 12 to 19

From the median frost dates of the NOAA stations assigned to the 3,025 ZIP codes in zone 7b, and the timing recommended by Cooperative Extension guides for potatoes.

Dates before the last frost assume the soil has thawed and is dry enough to work: a squeezed handful crumbles instead of sticking. After a late or wet spring, wait for that even if the date has passed.

Frost risk in zone 7b

Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 7b, the typical last frost ranges from about March 30 in the earliest tenth of ZIP codes to April 17 in the latest tenth, and the first fall frost from October 24 to November 18. For a typical place in the zone:

• March 20Risky: a later frost happens in 9 years out of 10
• April 5Typical: frost after this date in half of years
• April 21Safe: a later frost only 1 year in 10

Potatoes in zone 7b cities