Missoula, MT · zone 5a · ~144 frost-free days

When to plant a garden in Missoula.

In Missoula, the typical last spring frost lands around May 10 and the first fall frost around Oct 1, giving you about 144 frost-free days. Cool-season crops go out before the last frost; warm-season crops wait until after it.

The 2026 windows

Sow dates for Missoula, keyed to your frost.

CropStart indoorsSpring sow / set outFall sow
Tomato, slicingApr 5 to Jun 5May 17 to Jul 17
Lettuce, leafApr 2 to May 17Jul 18 to Sep 16
CarrotApr 2 to May 5Jul 6 to Aug 1
Bush BeanMay 10 to Jun 30Jun 17 to Jul 20
Cucumber, slicingMay 17 to Aug 16May 31 to Jul 1
Pepper, bellApr 14 to Jun 5May 26 to Jul 17
KaleFeb 19 to Mar 19Apr 2 to Apr 30Jul 1 to Aug 16
SpinachMar 19 to Apr 30Jul 18 to Sep 5

Missoula sits in Zone 5a, but two gardens in the same city can be a week or two apart. The planner works from your ZIP code's frost dates, not the zone, so the dates land right for your block, not the metro average.

Build your Missoula garden plan.

Tell the free planner what you want to eat and who you're feeding. It returns plant counts, spacing, and frost-safe sow dates for ZIP 59801 in about 60 seconds.