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Helena, MT planting calendar

When to plant vegetables in Helena, MT (USDA hardiness zone 4b). Typical last spring frost around May 9, 2027 (±10 days year to year), first fall frost around Sep 30, 2027 (±9 days).

Playing it safe? Spring frost holds off until about May 21, 2027 in roughly 9 years out of 10 — a good target for tender crops like tomatoes and peppers.

These dates are typical for the whole city. Enter your ZIP for frost dates from the station nearest you:

Month by month in Helena, MT

January

February

March

April

May

June

August

Understand your frost dates

More Montana planting calendars

ZIP codes in Helena

59601, 59602, 59626

Where these dates come from

Frost dates for Helena, MTare NOAA 1991–2020 climate normals from a station representative of the area, which covers 3 ZIP codes. Individual ZIP codes within it can run earlier or later.

Your exact dates depend on your address and microclimate. Schedules are guidance, not guarantees.