Ann Arbor, MI Lawn Care Calendar
In a typical year, put down crabgrass preventer in Ann Arbor between Apr 19 and May 8. The best time to overseed is between Aug 6 and Sep 25. The last spring frost usually comes around Apr 28. Most lawns here are cool-season grass (tall fescue, Kentucky bluegrass, ryegrass).
Typical lawn care dates in Ann Arbor
| Task | Typical window |
|---|---|
| Crabgrass preventer (pre-emergent)Crabgrass sprouts once soil stays above 55°F. Apply when soil reaches 50°F, before that happens. | Apr 19 – May 8 |
| Spring fertilizerA light feeding once soil warms past 55°F and the grass is actively growing. | May 1 – Jun 5 |
| Overseeding & seedingLate summer to early fall: seedlings need about 6–10 weeks of growth before the first frost. | Aug 6 – Sep 25 |
| Fall fertilizerThe most important feeding for cool-season grass, from early fall until soil cools to about 45°F. | Aug 12 – Nov 2 |
Median dates, 2016–2025, from NOAA weather data for Ann Arbor. This year's dates can differ by a few weeks.
Month-by-month lawn care in Ann Arbor
- JanuaryNo treatments due; mow as needed.
- FebruaryNo treatments due; mow as needed.
- MarchNo treatments due; mow as needed.
- AprilCrabgrass preventer (pre-emergent)
- MayCrabgrass preventer (pre-emergent)Spring fertilizer
- JuneSpring fertilizer
- JulyNo treatments due; mow as needed.
- AugustOverseeding & seedingFall fertilizer
- SeptemberOverseeding & seedingFall fertilizer
- OctoberFall fertilizer
- NovemberFall fertilizer
- DecemberNo treatments due; mow as needed.
Soil temperature in Ann Arbor by month
Average soil temperature 4 inches down, estimated from 2016–2025 weather. It bottoms out in January at 26°F and peaks in July at 73°F. Crabgrass preventer goes down when it reaches 50°F, usually around Apr 19.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 26°F | 27°F | 37°F | 46°F | 58°F | 68°F | 73°F | 71°F | 65°F | 54°F | 40°F | 31°F |
Ann Arbor lawn timing, year by year
Over the last 10 years, soil in Ann Arbor reached 50°F, the signal for crabgrass preventer, as early as Apr 7 (2021) and as late as May 7 (2022): 30 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 (Apr 28) and first fall frost (Oct 20), the growing season lasts about 175 days.
| Year | Crabgrass window opened | Last spring frost | First fall frost |
|---|---|---|---|
| 2025 | Apr 19 | Apr 17 | Oct 25 |
| 2024 | Apr 14 | Apr 26 | Oct 27 |
| 2023 | Apr 12 | Apr 27 | Oct 23 |
| 2022 | May 7 | Apr 29 | Oct 8 |
| 2021 | Apr 7 | May 1 | Oct 24 |
| 2020 | Apr 29 | May 13 | Oct 16 |
| 2019 | Apr 23 | Apr 15 | Oct 15 |
| 2018 | May 2 | Apr 30 | Oct 16 |
| 2017 | Apr 10 | May 9 | Oct 26 |
| 2016 | Apr 18 | Apr 24 | Oct 14 |
Estimated from daily temperatures for Ann Arbor. A dash means it didn't happen that year.
Frequently asked questions
When should I apply pre-emergent in Ann Arbor?
In a typical year, between Apr 19 and May 8. 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 Ann Arbor?
Early fall, typically Aug 6 – Sep 25, while soil cools from 65°F toward 50°F.
When is the last frost in Ann Arbor?
The median last spring frost is Apr 28 and the median first fall frost is Oct 20 (2016–2025).
How long is the growing season in Ann Arbor?
About 175 days, from the median last spring frost on Apr 28 to the median first fall frost on Oct 20 (2016–2025).
Lawn care guides
More Michigan lawn calendars
Nearby cities in other states
- Toledo, OH 45 miles away · crabgrass preventer Apr 19 – May 4
- Fort Wayne, IN 110 miles away · crabgrass preventer Apr 15 – Apr 28
- Cleveland, OH 118 miles away · crabgrass preventer Apr 20 – May 3
- South Bend, IN 135 miles away · crabgrass preventer Apr 19 – May 8