Missoula, Montana planting calendar and frost dates
Missoula is in USDA hardiness zone 5b. The last spring frost typically comes around May 10 and the first fall frost around October 1, giving about 143 frost-free days a year.
- Hardiness zone
- Zone 5b
- Typical last frost
- May 10
- Typical first frost
- October 1
- Frost-free season
- 143 days
Frost dates in Missoula
Last spring frost
- April 27Risky: frost later than this in 9 years out of 10
- May 10Typical: a later frost in half of years
- May 28Safe: a later frost only 1 year in 10
First fall frost
- September 16Risky: frost earlier than this 1 year in 10
- October 1Typical: an earlier frost in half of years
- October 15Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 143 days. Frost here means a low of 32°F at the weather station. A hard freeze (28°F), which damages most hardy crops too, typically ends around April 28 and returns around October 12.
NOAA U.S. Climate Normals 1991-2020 for Missoula 2 Ne, 2.2 miles NE of the city center and 212 feet higher. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.
What to plant each month in Missoula
January
Start indoors: onions
February
Start indoors: broccoli, cauliflower, collard greens, kale, leeks, onions, petunias, ranunculus
March
Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, chives, cilantro, collard greens, ginger, kale, leeks, lettuce, marigolds, nasturtiums, onions, oregano, parsley, petunias, ranunculus, rosemary, sage, snapdragons, spinach, swiss chard
Plant or sow outdoors: black-eyed susans, blueberries, garlic, grapes, grass seed, hollyhocks, onions, peas, poppies, raspberries, rhubarb, strawberries, turnips, wildflowers
April
Start indoors: basil, celery, cilantro, eggplants, ginger, marigolds, nasturtiums, peppers, ranunculus, spinach, swiss chard, tomatoes
Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, lettuce, onions, parsley, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, snapdragons, spinach, strawberries, swiss chard, turnips, wildflowers
May
Start indoors: basil, cantaloupes, cosmos, cucumbers, okra, pumpkins, tomatoes, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, beets, carrots, cauliflower, chives, cilantro, dahlias, dill, figs, garden mums, ginger, gladioli, grapes, green onions, kentucky bluegrass, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, perennial ryegrass, petunias, potatoes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, sweet peas, swiss chard, tall fescue, thyme
June
Start indoors: cosmos, cucumbers, okra, pumpkins, winter squash, zinnias, zucchini
Plant or sow outdoors: asparagus, basil, cantaloupes, cucumbers, eggplants, garden mums, ginger, green beans, green onions, kentucky bluegrass, peppers, perennial ryegrass, pumpkins, st. augustinegrass, sweet peas, tall fescue, tomatoes, watermelons, winter squash, zucchini
Plant for fall: brussels sprouts
July
Plant or sow outdoors: bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, green beans, green onions, okra, peanuts, peppers, pumpkins, st. augustinegrass, sweet potatoes, tomatoes, watermelons, winter squash, zinnias, zoysiagrass, zucchini
Plant for fall: bearded irises, beets, broccoli, brussels sprouts, cabbages, carrots, cauliflower, collard greens, daylilies, kale, lettuce, peas, radishes, snapdragons, spinach, swiss chard, turnips
August
Plant or sow outdoors: bermudagrass, centipedegrass, zinnias, zoysiagrass
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hydrangeas, kale, lettuce, lilies, ornamental alliums, peonies, radishes, roses, saffron, snapdragons, spinach, tulips, turnips
September
Plant for fall: crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, kale, lilies, ornamental alliums, peonies, radishes, saffron, tulips
October
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
Frost dates and zones by ZIP code in Missoula
All 5 of Missoula's main ZIP codes take their frost dates from Missoula 2 Ne, so the dates on this page apply across the city. Every one of them is in zone 5b.
Planting dates for popular crops in Missoula
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Apr 22 to May 6 | Jun 17 to Jul 1 | — |
| Strawberries | — | Mar 29 to Apr 12 | — |
| Lettuce | Mar 15 to 29 | May 3 to 17 | Jul 2 to Aug 6 |
| Cilantro | Mar 29 to Apr 12 | May 10 to 17 | — |
| Basil | Apr 29 to May 13 | Jun 17 to 24 | — |
| Potatoes | — | May 4 to 11 | — |
| Garlic | — | Mar 29 to Apr 12 | Oct 1 to 15 |
| Onions | Jan 18 to Mar 1 | Apr 12 to 26 | — |
| Cucumbers | May 20 to Jun 3 | Jun 17 to Jul 1 | — |
| Pumpkins | May 20 to Jun 3 | Jun 17 to Jul 1 | — |
| Peppers | Apr 1 to 29 | Jun 17 to Jul 1 | — |
| Carrots | — | Apr 19 to May 10 | Jul 9 to 30 |
| Sweet Potatoes | — | Jul 3 to 10 | — |
| Watermelons | May 13 to 27 | Jun 17 to Jul 1 | — |
| Sweet Corn | — | May 10 to 24 | — |
| Green Beans | — | Jun 17 to Jul 1 | — |
| Zucchini | May 20 to Jun 3 | Jun 17 to Jul 1 | — |
| Broccoli | Feb 22 to Mar 15 | Apr 12 to 26 | Jul 16 to Aug 13 |
| Peas | — | Mar 29 to Apr 12 | Jul 9 to 23 |
| Spinach | Mar 29 to Apr 5 | May 3 to 17 | Jul 23 to Aug 27 |
| Sunflowers | — | May 10 to 31 | — |
| Zinnias | Jun 22 to 29 | Jul 20 to Aug 3 | — |
| Tulips | — | — | Aug 20 to Oct 15 |
| Daffodils | — | — | Aug 20 to Oct 1 |
| Grass Seed | — | Mar 29 to Apr 12 | Aug 20 to Sep 3 |
Nearby cities
- Great Falls, MT zone 4b, last frost May 19
- Coeur d'Alene, ID zone 6b, last frost Apr 22
- Spokane Valley, WA zone 7a, last frost Apr 26
- Bozeman, MT zone 5a, last frost May 23
- Spokane, WA zone 6b, last frost Apr 26
- Pasco, WA zone 7a, last frost Apr 7
Planting in MontanaAbout zone 5bPrintable calendar for Missoula
Questions
When is the last frost in Missoula?
Around May 10 in a typical year, based on NOAA's 1991-2020 records for Missoula 2 Ne. There is still a 1 in 10 chance of frost after May 28.
What planting zone is Missoula in?
USDA hardiness zone 5b (2023 map). The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Missoula?
Start seeds indoors April 22 to May 6 and set plants out June 17 to July 1.
When is the first frost in Missoula?
Around October 1 in a typical year, and before September 16 about 1 year in 10.