Missoula, MT Lawn Care Calendar
In a typical year, put down crabgrass preventer in Missoula between May 10 and May 27. The best time to overseed is between Jul 18 and Sep 6. The last spring frost usually comes around May 9. Most lawns here are cool-season grass (tall fescue, Kentucky bluegrass, ryegrass).
Typical lawn care dates in Missoula
| Task | Typical window |
|---|---|
| Crabgrass preventer (pre-emergent)Crabgrass sprouts once soil stays above 55°F. Apply when soil reaches 50°F, before that happens. | May 10 – May 27 |
| Spring fertilizerA light feeding once soil warms past 55°F and the grass is actively growing. | May 20 – Jun 24 |
| Overseeding & seedingLate summer to early fall: seedlings need about 6–10 weeks of growth before the first frost. | Jul 18 – Sep 6 |
| Fall fertilizerThe most important feeding for cool-season grass, from early fall until soil cools to about 45°F. | Jul 29 – Oct 17 |
Median dates, 2016–2025, from NOAA weather data for Missoula. This year's dates can differ by a few weeks.
Month-by-month lawn care in Missoula
- JanuaryNo treatments due; mow as needed.
- FebruaryNo treatments due; mow as needed.
- MarchNo treatments due; mow as needed.
- AprilNo treatments due; mow as needed.
- MayCrabgrass preventer (pre-emergent)Spring fertilizer
- JuneSpring fertilizer
- JulyOverseeding & seedingFall fertilizer
- AugustOverseeding & seedingFall fertilizer
- SeptemberOverseeding & seedingFall fertilizer
- OctoberFall fertilizer
- NovemberNo treatments due; mow as needed.
- DecemberNo treatments due; mow as needed.
Soil temperature in Missoula by month
Average soil temperature 4 inches down, estimated from 2016–2025 weather. It bottoms out in January at 24°F and peaks in July at 69°F. Crabgrass preventer goes down when it reaches 50°F, usually around May 10.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 24°F | 26°F | 36°F | 43°F | 52°F | 60°F | 69°F | 68°F | 59°F | 46°F | 34°F | 27°F |
Missoula lawn timing, year by year
Over the last 10 years, soil in Missoula reached 50°F, the signal for crabgrass preventer, as early as Apr 20 (2016) and as late as May 26 (2022): 36 days apart. A fixed calendar date can't follow that, which is why the report above uses this year's soil temperature. Between the typical last spring frost (May 9) and first fall frost (Oct 1), the growing season lasts about 145 days.
| Year | Crabgrass window opened | Last spring frost | First fall frost |
|---|---|---|---|
| 2025 | May 8 | May 19 | Oct 6 |
| 2024 | May 11 | Jun 1 | Oct 1 |
| 2023 | Apr 30 | Apr 29 | Oct 25 |
| 2022 | May 26 | May 12 | Oct 17 |
| 2021 | May 14 | May 22 | Sep 18 |
| 2020 | Apr 29 | May 5 | Sep 9 |
| 2019 | May 11 | May 2 | Sep 30 |
| 2018 | May 5 | Apr 25 | Oct 8 |
| 2017 | May 22 | May 17 | Sep 24 |
| 2016 | Apr 20 | Apr 20 | Sep 13 |
Estimated from daily temperatures for Missoula. A dash means it didn't happen that year.
Frequently asked questions
When should I apply pre-emergent in Missoula?
In a typical year, between May 10 and May 27. Put it down when soil reaches 50°F, before it stays above 55°F and crabgrass starts sprouting. Early springs move this up by a week or more, so check this year's soil temperature above.
When is the best time to plant grass seed in Missoula?
Early fall, typically Jul 18 – Sep 6, while soil cools from 65°F toward 50°F.
When is the last frost in Missoula?
The median last spring frost is May 9 and the median first fall frost is Oct 1 (2016–2025).
How long is the growing season in Missoula?
About 145 days, from the median last spring frost on May 9 to the median first fall frost on Oct 1 (2016–2025).
Lawn care guides
More Montana lawn calendars
Nearby cities in other states
- Coeur d'Alene, ID 142 miles away · crabgrass preventer Apr 27 – May 18
- Spokane, WA 170 miles away · crabgrass preventer Apr 26 – May 15
- Boise, ID 249 miles away · crabgrass preventer Apr 10 – May 8
- Kennewick, WA 249 miles away · crabgrass preventer Mar 31 – May 3