When to plant in Lexington, MA
USDA Zone 6bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Lexington, Massachusetts — all computed from Lexington's nearest NOAA weather station.
In zone 6b, Lexington gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
The average last spring frost in Lexington is now 5 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
BEDFORD HANSCOM FLD · 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 Lexington’s own odds, recorded at BEDFORD HANSCOM FLD.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 23 | May 10 | Apr 28 | Sep 17 | Oct 1 | Oct 13 |
| 32°F | May 12 | Apr 28 | Apr 13 | Sep 28 | Oct 10 | Oct 28 |
| 28°F | Apr 29 | Apr 12 | Apr 1 | Oct 7 | Oct 25 | Nov 8 |
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 Lexington, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 12 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.
Lexington planting FAQ
When is the last spring frost in Lexington, MA?
Lexington's average last spring frost falls near April 28 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Lexington, MA?
The first fall frost in Lexington typically arrives around October 10 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Lexington in?
Lexington 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 Lexington?
Lexington has about 165 frost-free days — a moderate growing season — between the average last spring frost (April 28) and first fall frost (October 10).
When should I plant tomatoes in Lexington?
For Lexington, sow tomatoes indoors about March 3–March 17 and move the seedlings out around May 5, after the last spring frost.
Never miss a window in Lexington
An email when it’s time to start seeds, transplant, and sow — timed to Lexington’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Arlington · 6 km
- Waltham · 6 km
- Burlington · 7 km
- Belmont · 7 km
- Winchester · 7 km
- Woburn · 8 km
- Watertown · 9 km
- Medford · 10 km
Frost dates recorded at BEDFORD HANSCOM FLD, 6 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 Lexington, MA — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014702. Retrieved from https://blissgarden.com/massachusetts/lexington.