Bellingham, WA Lawn Care Calendar
In a typical year, put down crabgrass preventer in Bellingham between Apr 17 and May 20. The best time to overseed is between Aug 23 and Oct 12. The last spring frost usually comes around Mar 11. Most lawns here are cool-season grass (tall fescue, Kentucky bluegrass, ryegrass).
Typical lawn care dates in Bellingham
| 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 17 – May 20 |
| Spring fertilizerA light feeding once soil warms past 55°F and the grass is actively growing. | May 13 – Jun 17 |
| Overseeding & seedingLate summer to early fall: seedlings need about 6–10 weeks of growth before the first frost. | Aug 23 – Oct 12 |
| Fall fertilizerThe most important feeding for cool-season grass, from early fall until soil cools to about 45°F. | Jul 15 – Nov 10 |
Median dates, 2016–2025, from NOAA weather data for Bellingham. This year's dates can differ by a few weeks.
Month-by-month lawn care in Bellingham
- 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
- JulyFall fertilizer
- AugustOverseeding & seedingFall fertilizer
- SeptemberOverseeding & seedingFall fertilizer
- OctoberOverseeding & seedingFall fertilizer
- NovemberFall fertilizer
- DecemberNo treatments due; mow as needed.
Soil temperature in Bellingham by month
Average soil temperature 4 inches down, estimated from 2016–2025 weather. It bottoms out in February at 40°F and peaks in August at 64°F. Crabgrass preventer goes down when it reaches 50°F, usually around Apr 17.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 41°F | 40°F | 44°F | 49°F | 55°F | 59°F | 63°F | 64°F | 60°F | 52°F | 46°F | 41°F |
Bellingham lawn timing, year by year
Over the last 10 years, soil in Bellingham reached 50°F, the signal for crabgrass preventer, as early as Jan 30 (2024) and as late as May 15 (2022): 105 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 (Mar 11) and first fall frost (Nov 6), the growing season lasts about 240 days.
| Year | Crabgrass window opened | Last spring frost | First fall frost |
|---|---|---|---|
| 2025 | Apr 7 | Mar 7 | Dec 1 |
| 2024 | Jan 30 | Mar 8 | Dec 4 |
| 2023 | Apr 28 | Mar 26 | Oct 26 |
| 2022 | May 15 | Mar 11 | Nov 3 |
| 2021 | Apr 17 | Apr 12 | Nov 17 |
| 2020 | Apr 16 | Mar 19 | Oct 26 |
| 2019 | Apr 2 | Mar 11 | Oct 10 |
| 2018 | Apr 25 | Mar 26 | Nov 8 |
| 2017 | Apr 18 | Mar 1 | Nov 3 |
| 2016 | Apr 1 | Jan 16 | Dec 7 |
Estimated from daily temperatures for Bellingham. A dash means it didn't happen that year.
Frequently asked questions
When should I apply pre-emergent in Bellingham?
In a typical year, between Apr 17 and May 20. 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 Bellingham?
Early fall, typically Aug 23 – Oct 12, while soil cools from 65°F toward 50°F.
When is the last frost in Bellingham?
The median last spring frost is Mar 11 and the median first fall frost is Nov 6 (2016–2025).
How long is the growing season in Bellingham?
About 240 days, from the median last spring frost on Mar 11 to the median first fall frost on Nov 6 (2016–2025).
Lawn care guides
More Washington lawn calendars
Nearby cities in other states
- Portland, OR 223 miles away · crabgrass preventer Apr 1 – May 5
- Salem, OR 265 miles away · crabgrass preventer Apr 1 – May 9
- Coeur d'Alene, ID 273 miles away · crabgrass preventer Apr 27 – May 18
- Eugene, OR 326 miles away · crabgrass preventer Apr 5 – May 13