When to plant in Cambridge, MA
USDA Zone 6bCambridge, Massachusetts frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 6b means Cambridge sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
The average first fall frost in Cambridge is now 7 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
JAMAICA PLAIN · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Cambridge’s own odds, recorded at JAMAICA PLAIN.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 16 | May 2 | Apr 20 | Sep 30 | Oct 10 | Oct 25 |
| 32°F | May 3 | Apr 19 | Apr 6 | Oct 8 | Oct 23 | Nov 5 |
| 28°F | Apr 21 | Apr 5 | Mar 25 | Oct 19 | Nov 3 | Nov 19 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Cambridge, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 16 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Cambridge planting FAQ
When is the last spring frost in Cambridge, MA?
Plan for the last spring frost in Cambridge around April 19 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Cambridge, MA?
The first fall frost in Cambridge typically arrives around October 23 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Cambridge in?
Cambridge is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Cambridge?
There are roughly 187 frost-free days in Cambridge (a moderate growing season), running from the average last frost around April 19 to the first fall frost near October 23.
When should I plant tomatoes in Cambridge?
In Cambridge, start tomato seeds indoors around February 22–March 8, then transplant seedlings outdoors around April 26 once the danger of frost has passed.
Never miss a window in Cambridge
An email when it’s time to start seeds, transplant, and sow — timed to Cambridge’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at JAMAICA PLAIN, 8 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Cambridge, MA — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00193890. Retrieved from https://blissgarden.com/massachusetts/cambridge.