Montana Gardening Guide (2026)

Short, dry, cold season at altitude. Start indoors; wind protection helps.

Garden countdownToday: Aug 19

USDA 2023 zones + NOAA 1991-2020 frost normals. Estimates — check your local forecast before planting.

USDA hardiness zone
36
Region
Mountain
Typical last spring frost
05/20
Typical first fall frost
09/20
Frost-free season
123 days
Lawn grass type
Cool-season

Quick answer (Montana): Most of the state gardens in USDA zones 36 with about a 123-day frost-free window. Plan around the typical last frost of 05/20; start warm-season crops indoors ~6 weeks earlier. Source: USDA Plant Hardiness Zone Map (2023) + state cooperative extension typical freeze dates.

Your Montana planting calendar

Pre-filled for Montana. Pick a crop to see indoor start, sow/transplant, and harvest dates you can print.

In Montana (typical zone 36, last frost ≈ May 20, first frost ≈ Sep 20, 123-day season), your Tomato plan:

Start seeds indoors
Apr 8
Sow / transplant outdoors
Jun 3
First harvest
Aug 12
Spacing / depth
24″ / 0.25

Month-by-month (Montana, 2026)

MonthAction
Jan
Feb
Mar
AprStart indoors
May
JunSow · Transplant
Jul
AugHarvest
Sep
Oct
Nov
Dec

Start indoors 6 weeks before last frost; transplant after soil warms. Zones 313 suitable. Dates are typical; confirm with your county extension and watch the 10-day forecast.

Lawns in Montana

Best grass types for your climate:

Kentucky BluegrassTall FescuePerennial RyegrassFine Fescue

Open the lawn care scheduler →

Common pests in Montana

The pests most reported in your region, with organic-first treatments:

GrasshopperCutwormAphids

Grasshopper

Targets
Vegetables, ornamentals, young trees
Signs
Chewed leaves and stems; active jumpers in hot dry weather.
Organic / IPM first
Row covers; chickens; neem; beneficial nematodes.
Chemical option (follow label)
Nosema locustae bait (slow) or carbaryl for outbreaks.
Prevention
Trap crops; reduce weedy borders; till in fall.

What grows well in Montana

Crops suitable for zones 36:

CropTypeSpacingDays to harvest
TomatoWarm-season2470
PepperWarm-season1875
LettuceCool-season845
CarrotCool-season365
Green BeansWarm-season455
SpinachCool-season640
CucumberWarm-season1255
ZucchiniWarm-season3650
KaleCool-season1255
BroccoliCool-season1870

Figures are typical (30-year normals) from USDA and state extension services. Always confirm your local last/first freeze and product labels with your county extension before acting.