When to plant tomatoes in Idaho

Tomatoes
Plant out in Boise City
May 1–May 15

Across Idaho the window opens between April 13 and May 19. Find your city below; the dates follow each town's own average last frost.

Start indoors, Boise City
Feb 27–Mar 13
Plant out, Boise City
May 1–May 15
Last sowing for a harvest
Jul 14
Last frost, Boise City
Apr 24

Start seeds indoors 6–8 weeks before the last frost; plant out 1–3 weeks after the last frost. Wait for nights that stay above 50°F. A cold snap after transplanting stalls tomatoes for weeks.

Tomatoes planting dates by city

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
JanFebMarAprMayJunJulAugSepOctNovDec
Boise CityMay 1–May 15
MeridianMay 1–May 15
NampaMay 6–May 20
CaldwellMay 6–May 20
Idaho FallsMay 16–May 30
PocatelloMay 9–May 23
Coeur d'AleneApr 29–May 13
Twin FallsMay 7–May 21
Post FallsApr 29–May 13
RexburgMay 19–Jun 2
LewistonApr 13–Apr 27
EagleMay 6–May 20
KunaMay 1–May 15
StarMay 6–May 20
AmmonMay 16–May 30

Questions

When should I plant tomatoes in Idaho?

In Boise City, plant out from May 1 to May 15. Across Idaho the window opens between April 13 and May 19, depending on the local last frost.

How is this date worked out?

Start seeds indoors 6–8 weeks before the last frost; plant out 1–3 weeks after the last frost. Frost dates are NOAA 1991–2020 averages for the weather station nearest each city.

More for Idaho

Tomatoes in other states

Frost dates for every city in Idaho