When to plant Sweet corn in Idaho

In spring, from Apr 10 – June 1 in Lewiston to May 15 – June 1 in Garden City.

In fall, June 1 – July 1.

USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.

Sweet corn planting dates by place in Idaho
PlaceSpringFall
AmmonMay 10 – June 1June 1 – July 1
BlackfootMay 10 – June 15June 1 – July 1
Boise CityApr 25 – June 15June 1 – July 20
BurleyMay 10 – June 1June 1 – July 1
CaldwellMay 10 – June 15June 1 – July 10
ChubbuckMay 15 – June 1June 1 – July 1
Coeur d'AleneApr 25 – June 15June 1 – July 20
EagleMay 10 – June 15June 1 – July 20
Garden CityMay 15 – June 1June 1 – July 10
HaydenApr 25 – June 15June 1 – July 20
Idaho FallsMay 10 – June 1June 1 – July 1
JeromeMay 10 – June 15June 1 – July 10
KunaApr 25 – June 15June 1 – July 20
LewistonApr 10 – June 1June 1 – Aug 1
MeridianApr 25 – June 15June 1 – July 20
MiddletonMay 10 – June 15June 1 – July 10
MoscowMay 10 – June 15June 1 – July 1
Mountain HomeMay 10 – June 15June 1 – July 10
NampaMay 10 – June 15June 1 – July 10
PocatelloMay 10 – June 15June 1 – July 10
Post FallsApr 25 – June 15June 1 – July 20
RathdrumApr 25 – June 15June 1 – July 20
RexburgMay 10 – June 1June 1 – July 1
SandpointMay 10 – June 1June 1 – July 1
StarMay 10 – June 15June 1 – July 10
Twin FallsMay 10 – June 15June 1 – July 10

Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for sweet corn.