Frost Dates for Missoula, MT 59804

Missoula has 6 ZIP codes. The Missoula, MT frost page lists all of them with their dates.

Last spring frost May 26 · First fall frost September 18 · 115 frost-free days · USDA Zone 5b

ZIP 59804 has about 8,120 people, one of 6 ZIP codes in Missoula.

Short season: 115 frost-free days. Spring frost risk spans May 6–June 15 (40 days). Fall frost risk spans September 4–October 2 (28 days).

Frost probability for 59804

Frost10%50%90%
Spring (last frost)June 15May 26May 6
Fall (first frost)September 4September 18October 2

Dates come from NOAA 1971–2000 freeze probabilities at MISSOULA INTL AP (12.1 km away); the 50% date is the median year.

Which crops fit a 115-day season in Missoula

In Missoula (115 frost-free days, a short season), 32 of 56 planner crops fit outright, 15 get two plantings, 8 need an indoor start, 1 crop is perennial.

CropStart indoorsPlant out / sowDays you haveVerdictLast sow date
TomatoApr 21Jun 9–Jun 1673head-start: Even planted out Jun 9, the outdoor season is about 7 days short; choose an early variety or grow under cover.—
PepperApr 14Jun 9–Jun 1673head-start: Even planted out Jun 9, the outdoor season is about 2 days short; choose an early variety or grow under cover.—
LettuceMar 31Apr 28–May 5150two-plantings: Plant Apr 28 and again by Jul 28; both mature before Sep 25.Jul 28
Carrots—May 5–May 12157fits: 70 days to maturity, 157 available after May 5.Jul 17
CucumberMay 5Jun 9–Jun 1687fits: 60 days to maturity, 87 available after Jun 9.Jun 22
Beans—Jun 2–Jun 16101fits: 60 days to maturity, 101 available after Jun 2.Jun 29
Peas—Mar 31–Jun 9178fits: 65 days to maturity, 178 available after Mar 31.Jul 8
ZucchiniMay 12Jun 9–Jun 1687fits: 55 days to maturity, 87 available after Jun 9.Jun 27
OnionMar 3Apr 28–May 12150fits: 100 days to maturity, 150 available after Apr 28.—
Spinach—Mar 31–May 19192two-plantings: Plant Mar 31 and again by Aug 16; both mature before Oct 9.Aug 16
KaleMar 17Apr 28–May 12164two-plantings: Plant Apr 28 and again by Aug 1; both mature before Oct 9.Aug 1
BroccoliMar 31Apr 28–May 12150fits: 80 days to maturity, 150 available after Apr 28.Jun 23
CabbageMar 31Apr 28–May 12164fits: 70 days to maturity, 164 available after Apr 28.Jul 17
Radish—Mar 31–Jun 23178two-plantings: Plant Mar 31 and again by Aug 17; both mature before Sep 25.Aug 17
Beets—Mar 31–Jun 23178two-plantings: Plant Mar 31 and again by Jul 18; both mature before Sep 25.Jul 18
Potatoes—May 12–May 19136fits: 90 days to maturity, 136 available after May 12.—
Garlic—Sep 18220overwinter: Plant Sep 18 to Oct 9; harvest the following summer.Oct 9
Strawberry—Apr 21–Jun 16171perennial: A perennial: plant Apr 21; it fruits from the following year and keeps producing for several years.—
CornApr 28Jun 2–Jun 987fits: 75 days to maturity, 87 available after Jun 2.—
PumpkinMay 12Jun 9–Jun 980head-start: Even planted out Jun 9, the outdoor season is about 20 days short; choose an early variety or grow under cover.—
CauliflowerApr 14May 19–Jun 2129fits: 75 days to maturity, 129 available after May 19.Jun 28
Swiss ChardMar 31May 12–May 12136two-plantings: Plant May 12 and again by Jul 18; both mature before Sep 25.Jul 18
Arugula—Mar 31–Jun 23192two-plantings: Plant Mar 31 and again by Aug 16; both mature before Oct 9.Aug 16
Brussel SproutsMar 31Apr 28–May 12164fits: 100 days to maturity, 164 available after Apr 28.Jun 17
Butternut SquashMay 12Jun 9–Jun 1680head-start: Even planted out Jun 9, the outdoor season is about 20 days short; choose an early variety or grow under cover.—
EggplantApr 7Jun 9–Jun 1673fits: 70 days to maturity, 73 available after Jun 9.—
OkraApr 28Jun 2–Jun 994fits: 55 days to maturity, 94 available after Jun 2.Jun 27
BasilApr 21Jun 16–Jun 1680fits: 60 days to maturity, 80 available after Jun 16.Jun 22
Cilantro—Apr 28–May 19150two-plantings: Plant Apr 28 and again by Jul 23; both mature before Sep 25.Jul 23
ParsleyMar 17Jun 2–Jun 9115fits: 70 days to maturity, 115 available after Jun 2.Jul 3
CeleryMar 17Jun 2–Jun 16115head-start: Even planted out Jun 2, the outdoor season is about 5 days short; choose an early variety or grow under cover.—
ScallionsMar 17Apr 28–May 12164two-plantings: Plant Apr 28 and again by Jul 27; both mature before Oct 9.Jul 27
Turnip—Apr 28–May 12164two-plantings: Plant Apr 28 and again by Aug 6; both mature before Oct 9.Aug 6
Kohlrabi—Apr 14–Apr 28178two-plantings: Plant Apr 14 and again by Aug 1; both mature before Oct 9.Aug 1
Bok ChoyApr 28May 19–May 26129two-plantings: Plant May 19 and again by Jul 28; both mature before Sep 25.Jul 28
CollardsMar 17Apr 28–May 12164two-plantings: Plant Apr 28 and again by Jul 27; both mature before Oct 9.Jul 27
CantaloupeMay 12Jun 9–Jun 1673head-start: Even planted out Jun 9, the outdoor season is about 12 days short; choose an early variety or grow under cover.—
ChivesMar 3Jun 2–Jun 9129fits: 90 days to maturity, 129 available after Jun 2.—
Dill—Mar 31–Jun 23178two-plantings: Plant Mar 31 and again by Jul 18; both mature before Sep 25.Jul 18
OreganoMar 17Jun 2–Jun 9129fits: 80 days to maturity, 129 available after Jun 2.—
RosemaryMar 3Jun 2–Jun 9115fits: 80 days to maturity, 115 available after Jun 2.—
SageMar 31Jun 2–Jun 9129fits: 75 days to maturity, 129 available after Jun 2.—
ThymeMar 17Jun 2–Jun 9129fits: 90 days to maturity, 129 available after Jun 2.—
CalendulaApr 14May 12–May 26136two-plantings: Plant May 12 and again by Jul 23; both mature before Sep 25.Jul 23
CosmosApr 28May 26–Jun 9101fits: 60 days to maturity, 101 available after May 26.Jun 22
LavenderMar 3May 26–Jun 9136fits: 90 days to maturity, 136 available after May 26.—
MarigoldsApr 14May 26–Jun 2101fits: 50 days to maturity, 101 available after May 26.Jul 2
MelonsMay 12Jun 9–Jun 1673head-start: Even planted out Jun 9, the outdoor season is about 12 days short; choose an early variety or grow under cover.—
Mint—May 26–Jun 9136fits: 90 days to maturity, 136 available after May 26.—
NasturtiumsApr 28May 26–Jun 2101fits: 55 days to maturity, 101 available after May 26.Jun 27
Pole Beans—Jun 2–Jun 1694fits: 65 days to maturity, 94 available after Jun 2.Jun 17
Spaghetti SquashMay 12Jun 9–Jun 1680head-start: Even planted out Jun 9, the outdoor season is about 10 days short; choose an early variety or grow under cover.—
Sunflowers—May 26–Jun 9101fits: 70 days to maturity, 101 available after May 26.Jun 12
TomatillosMar 31Jun 2–Jun 980fits: 75 days to maturity, 80 available after Jun 2.—
WatermelonMay 12Jun 2–Jun 980fits: 80 days to maturity, 80 available after Jun 2.—
Yellow SquashMay 12Jun 9–Jun 1687fits: 55 days to maturity, 87 available after Jun 9.Jun 27
ZinniasApr 28May 26–Jun 9101fits: 60 days to maturity, 101 available after May 26.Jun 22

Month by month in Missoula

MonthWhat to do
JanuaryPlan your garden layout and order seeds. Research varieties suited to your frost dates.
FebruaryStart the slowest-growing crops indoors: onions, leeks, and celery (10–12 weeks before last frost).
MarchStart indoors: Chives (Mar 3), Lavender (Mar 3), Onion (Mar 3), Rosemary (Mar 3), Celery (Mar 17), Collards (Mar 17), +12 more. Direct sow from: Arugula (Mar 31), Beets (Mar 31), Dill (Mar 31), Peas (Mar 31), Radish (Mar 31), Spinach (Mar 31).
AprilStart indoors: Eggplant (Apr 7), Calendula (Apr 14), Cauliflower (Apr 14), Marigolds (Apr 14), Pepper (Apr 14), Basil (Apr 21), +7 more. Direct sow from: Kohlrabi (Apr 14), Cilantro (Apr 28), Turnip (Apr 28). Transplant from: Broccoli (Apr 28), Brussel Sprouts (Apr 28), Cabbage (Apr 28), Collards (Apr 28), Kale (Apr 28), Lettuce (Apr 28), +2 more. Plant: Strawberry (Apr 21).
MayStart indoors: Cucumber (May 5), Butternut Squash (May 12), Cantaloupe (May 12), Melons (May 12), Pumpkin (May 12), Spaghetti Squash (May 12), +3 more. Direct sow from: Carrots (May 5), Potatoes (May 12), Sunflowers (May 26). Transplant from: Calendula (May 12), Swiss Chard (May 12), Bok Choy (May 19), Cauliflower (May 19), Cosmos (May 26), Lavender (May 26), +4 more. Last frost around May 26.
JuneDirect sow from: Beans (Jun 2), Pole Beans (Jun 2). Transplant from: Celery (Jun 2), Chives (Jun 2), Corn (Jun 2), Okra (Jun 2), Oregano (Jun 2), Parsley (Jun 2), +17 more. Last sowing dates: Sunflowers (Jun 12), Brussel Sprouts (Jun 17), Pole Beans (Jun 17), Basil (Jun 22), Cosmos (Jun 22), Cucumber (Jun 22), +8 more.
JulyLast sowing dates: Marigolds (Jul 2), Parsley (Jul 3), Peas (Jul 8), Cabbage (Jul 17), Carrots (Jul 17), Beets (Jul 18), +8 more.
AugustLast sowing dates: Kale (Aug 1), Kohlrabi (Aug 1), Turnip (Aug 6), Arugula (Aug 16), Spinach (Aug 16), Radish (Aug 17).
SeptemberDirect sow from: Garlic (Sep 18). First frost around September 18.
OctoberLast sowing dates: Garlic (Oct 9).
NovemberClean up spent plants. Add compost to beds. Rest, review, and plan next year's garden.
DecemberClean up spent plants. Add compost to beds. Rest, review, and plan next year's garden.

Frequently Asked Questions

What is the last frost date for Missoula, MT (ZIP 59804)?

The median last spring frost date for Missoula, MT (ZIP code 59804) is around May 26. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area. One year in ten frost ends before May 6; one in ten it runs past June 15.

What is the first fall frost date in Missoula, MT?

The median first fall frost date for Missoula, MT is around September 18. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses. The first frost arrives around September 4 in the earliest one-in-ten years, so cover tomatoes and peppers from then.

How long is the growing season in Missoula, MT?

The frost-free growing season in Missoula is about 115 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side. In Missoula (115 frost-free days, a short season), 32 of 56 planner crops fit outright, 15 get two plantings, 8 need an indoor start, 1 crop is perennial.

What USDA hardiness zone is Missoula, MT?

Missoula, MT is in USDA hardiness zone 5b (2023 USDA Plant Hardiness Zone Map). Zones come from the average coldest winter temperature, so they tell you which perennials survive the winter; the frost dates on this page tell you when to plant.

When should I start tomatoes indoors in Missoula, MT?

Start tomatoes indoors Apr 21 and plant out Jun 9 in Missoula. The planner uses the local median last frost and this crop's indoor-start and transplant offsets.

How many plantings of lettuce fit in Missoula?

Two: plant Apr 28 and again by Jul 28; both mature before Sep 25.

When do I plant garlic in Missoula?

Sep 18 to Oct 9; it overwinters and is ready the following summer.

Can I grow Celery in Missoula?

Yes, with help. Even planted out Jun 2, the outdoor season is about 5 days short; choose an early variety or grow under cover.

Which nearby ZIP has a longer season?

Polson (ZIP 59860) has 144 frost-free days, 29 more than Missoula (ZIP 59804). See Polson ZIP 59860 frost dates

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