Idaho · zones 5b–7b
When to plant cucumbers in Idaho.
Sow between May 18 to Aug 17 in a typical year, keyed to Idaho's median last frost around May 11. A second, fall sowing fits May 28 to Jun 28. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Cucumbers dates for a typical Idaho season.
Direct sow
May 18 to Aug 17
Keyed to the ~May 11 last frost. Sow 1" deep, 12" apart.
Fall round
May 28 to Jun 28
Counted back from the ~Sep 28 first frost.
Harvest
~60 days later
~5 lb per plant over ~5 weeks.
Idaho spans more than one climate: Zone 6 is the most common zone, but the state runs 5b to 7b. That's why the planner works from your ZIP code's frost dates, not your zone — mountain and coastal gardens in the same state can be three weeks apart.