When to plant in Stony Brook, NY
USDA Zone 7bStony Brook, New York frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 7b means many perennials and even some tender shrubs overwinter in Stony Brook, while your frost dates still decide when annuals go out.
The average last spring frost in Stony Brook is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
SETAUKET STRONG · 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 Stony Brook’s own odds, recorded at SETAUKET STRONG.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 15 | Apr 30 | Apr 15 | Oct 14 | Oct 29 | Nov 10 |
| 32°F | May 4 | Apr 15 | Apr 1 | Oct 27 | Nov 10 | Nov 24 |
| 28°F | Apr 19 | Mar 31 | Mar 14 | Nov 9 | Nov 21 | Dec 5 |
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 Stony Brook, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 13 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.
Stony Brook planting FAQ
When is the last spring frost in Stony Brook, NY?
Plan for the last spring frost in Stony Brook around April 15 (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 Stony Brook, NY?
The first fall frost in Stony Brook typically arrives around November 10 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Stony Brook in?
Stony Brook is in USDA hardiness zone 7b. In zone 7b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Stony Brook?
There are roughly 209 frost-free days in Stony Brook (a moderate growing season), running from the average last frost around April 15 to the first fall frost near November 10.
When should I plant tomatoes in Stony Brook?
In Stony Brook, start tomato seeds indoors around February 18–March 4, then transplant seedlings outdoors around April 22 once the danger of frost has passed.
Never miss a window in Stony Brook
An email when it’s time to start seeds, transplant, and sow — timed to Stony Brook’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- East Setauket · 3 km
- St. James · 4 km
- Lake Grove · 6 km
- Centereach · 6 km
- Terryville · 7 km
- Nesconset · 7 km
- Selden · 8 km
- Lake Ronkonkoma · 9 km
Frost dates recorded at SETAUKET STRONG, 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 Stony Brook, NY — Frost Dates & Zone 7b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00307633. Retrieved from https://blissgarden.com/new-york/stony-brook.