What to do in Bellingham now
Bellingham is in the transition zone, where both cool- and warm-season lawns grow. Dates are typical for this spot, worked out from 23 years of weather at Bellingham Intl Ap; each status uses this year's soil estimates.
Cool-season: tall fescue, Kentucky bluegrass, perennial ryegrass, fine fescue
- Crabgrass pre-emergent Closed May 4 Typical: Apr 18 – May 152-inch soil held 55°F for a week from May 4, so crabgrass was sprouting. Next window: about Apr 18 – May 15, 2027.
- Seed or overseed Too late this fall Typical: Aug 10 – Oct 104-inch soil fell below 50°F on Oct 26; new seedlings rarely establish now. Seed next fall from about Aug 10, or dormant-seed once soil is near freezing so seed sprouts in spring.
- Late-fall feeding Last call · about 34 days Typical: Nov 3 – Dec 7Top growth has slowed but roots keep feeding until 4-inch soil cools to about 40°F, typically Dec 7. A final nitrogen feeding now goes to the roots.
Warm-season: bermudagrass, zoysia, St. Augustine, centipede, bahia
- Crabgrass pre-emergent Closed May 4 Typical: Apr 18 – May 152-inch soil held 55°F for a week from May 4, so crabgrass was sprouting. Next window: about Apr 18 – May 15, 2027.
- Seed or sod Wait for late spring Typical: Jun 29 – Aug 10Warm-season seed needs 4-inch soil at 65°F or more, and seedlings need the rest of summer to establish. Next window opens about Jun 29.
- Fall pre-emergent (Poa annua) Germinating since Aug 10 Typical: By Aug 104-inch soil fell below 70°F on Aug 10, when annual bluegrass begins to sprout. A pre-emergent now only stops later flushes; plan to apply by about Aug 10 next year.
- Dormancy and last feeding Dormant since about Oct 15 Typical: Around Oct 104-inch soil has stayed under 55°F since Oct 15, so warm-season grass is going brown. It is too late to fertilize; feed again after spring green-up, once soil holds 65°F (typically Jun 29).
The last 60 days and the week ahead
Bellingham soil is 5° cooler than normal for Nov 3, cooler than on 84% of those dates since 2005, and 2° cooler than a year ago.
The green line is our estimate of the daily average soil temperature 2 inches down, driven by temperatures at Bellingham Intl Ap, 7.2 km from the city center. The dashed part runs the National Weather Service forecast through the same model. Hover or tap for any day.
2-inch soil, estimated From the NWS forecast Normal Normal range (8 years in 10)
Show the numbers
| Date | 2-inch soil | 4-inch soil | Air high / low | Normal (2 in) |
|---|---|---|---|---|
| Oct 20 | 50° | 52° | 62° / 33° | 52° |
| Oct 21 | 49° | 51° | 62° / 35° | 51° |
| Oct 22 | 48° | 50° | 54° / 39° | 51° |
| Oct 23 | 48° | 50° | 58° / 34° | 51° |
| Oct 24 | 46° | 48° | 48° / 35° | 50° |
| Oct 25 | 47° | 49° | 53° / 45° | 50° |
| Oct 26 | 47° | 49° | 54° / 43° | 49° |
| Oct 27 | 47° | 49° | 51° / 44° | 49° |
| Oct 28 | 47° | 49° | 52° / 40° | 49° |
| Oct 29 | 47° | 48° | 51° / 42° | 48° |
| Oct 30 | 46° | 48° | 49° / 38° | 48° |
| Oct 31 | 45° | 47° | 53° / 32° | 48° |
| Nov 1 | 43° | 45° | 50° / 29° | 48° |
| Nov 2 | 42° | 44° | 52° / 29° | 48° |
| Nov 3 | 43° | 45° | 54° / 36° | 48° |
| Nov 4 (forecast) | 46° | 47° | 59° / 47° | 47° |
| Nov 5 (forecast) | 48° | 48° | 57° / 46° | 47° |
| Nov 6 (forecast) | 48° | 49° | 55° / 46° | 47° |
| Nov 7 (forecast) | 50° | 51° | 62° / 49° | 47° |
| Nov 8 (forecast) | 49° | 50° | 54° / 41° | 47° |
| Nov 9 (forecast) | 49° | 50° | 54° / 46° | 47° |
Which grass grows in Bellingham
With January averaging 40°F, Bellingham sits in the transition zone. Tall fescue is the common cool-season choice; bermudagrass and zoysia are the common warm-season ones. Use the switch above to see the calendar for yours.
Bellingham soil through the year
Weekly 2-inch estimates for 2026 so far against 2025 and the normal for each week. The red lines mark 50°F, when crabgrass pre-emergent should be down, and 65°F, when warm-season seed sprouts well.
2026 2025 Normal (2005–2025) 8 years in 10
Normal by month
| Month | 2 in | 4 in | Air |
|---|---|---|---|
| Jan | 39° | 41° | 40° |
| Feb | 40° | 41° | 42° |
| Mar | 44° | 45° | 45° |
| Apr | 49° | 50° | 50° |
| May | 56° | 57° | 56° |
| Jun | 61° | 62° | 60° |
| Jul | 65° | 67° | 64° |
| Aug | 66° | 67° | 64° |
| Sep | 60° | 62° | 59° |
| Oct | 52° | 54° | 51° |
| Nov | 44° | 46° | 45° |
| Dec | 39° | 41° | 40° |
Soil: average of our daily estimates, 2005–2025. Air: NOAA 1991–2020 normals for the station.
Typical lawn dates in Bellingham
Each date is when the soil estimate (or the air, for freezes) crossed the threshold, year by year since 2005. “Early” and “late” are the 10th and 90th percentile years, so 8 years in 10 fall between them.
| Event | Typical | 2026 |
|---|---|---|
| Last spring freeze (32°F) | Apr 13 | Apr 9 |
| Crabgrass model: 250 growing degree days | Jan 28 | Jan 28 |
| Pre-emergent window opens (2-inch soil 50°F) | Apr 18 | Apr 22 |
| Crabgrass begins to sprout (2-inch soil 55°F) | May 15 | May 4 |
| Cool-season lawns start growing (4-inch soil 55°F) | May 11 | May 3 |
| Warm-season seeding opens (4-inch soil 65°F) | Jun 29 | Jun 23 |
| Cool-season seeding opens (4-inch soil under 70°F) | Aug 10 | Aug 10 |
| Cool-season seeding ends (4-inch soil under 55°F) | Oct 10 | Oct 15 |
| Warm-season grass goes dormant (4-inch under 55°F) | Oct 10 | Oct 15 |
| First fall freeze (32°F) | Oct 26 | Oct 12 |
| Roots stop feeding (4-inch soil under 40°F) | Dec 7 | not yet |
Where these numbers come from
There is no soil sensor in most cities, so we estimate it. Shallow soil follows air temperature with a lag of a few days, and runs a little warmer than the air in fall. We fitted that relationship to 190 USDA soil-sensor stations; on years held out of the fit, the estimate was off by 3.3°F on an average day, and it put the spring 55°F date within a median of 3 days. Read the methodology.
Weather: RCC ACIS station KBLI (BELLINGHAM INTL AP), daily data since 1949. Forecast: National Weather Service, SEW office, issued Nov 4, 2026, 1:26 AM EST. Last observed day: Nov 3, 2026.
Bellingham questions
What is the soil temperature in Bellingham today? Our estimate for Nov 3 is 43°F at 2 inches and 45°F at 4 inches, as a daily average. Early-morning soil runs a few degrees cooler than that, and afternoon soil warmer.
When should I put down crabgrass pre-emergent in Bellingham? Apply when 2-inch soil holds about 50°F and before it holds 55°F. That has typically been Apr 18 to May 15 in Bellingham. For 2026 the window closed on May 4.
When can I seed bermudagrass in Bellingham? Wait for late spring. Warm-season seed needs 4-inch soil at 65°F or more, and seedlings need the rest of summer to establish. Next window opens about Jun 29.
Is it too late to fertilize in Bellingham? Dormant since about Oct 15. 4-inch soil has stayed under 55°F since Oct 15, so warm-season grass is going brown. It is too late to fertilize; feed again after spring green-up, once soil holds 65°F (typically Jun 29).
When is the last frost in Bellingham? The last 32°F night of spring has typically come around Apr 13, and as late as Apr 27 in 1 year in 10. The first fall freeze typically arrives around Oct 26.
Why 2 inches and 4 inches? Crabgrass and most weed seeds sprout in the top inch or two, so pre-emergent timing follows 2-inch soil. Grass seed and roots respond to the slightly steadier soil at about 4 inches.
How accurate is this? It is a model, not a probe in your yard. Expect about 3–4°F of difference on a given day; shade, slope, mulch and irrigation all move real soil. The dates and trends are more reliable than any single day.