When to plant in Ansonia, CT
USDA Zone 6bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Ansonia, Connecticut — all computed from Ansonia's nearest NOAA weather station.
In zone 6b, Ansonia gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
ANSONIA 1 NE · 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 Ansonia’s own odds, recorded at ANSONIA 1 NE.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 22 | May 8 | Apr 24 | Sep 27 | Oct 7 | Oct 21 |
| 32°F | May 10 | Apr 25 | Apr 11 | Oct 4 | Oct 17 | Nov 1 |
| 28°F | Apr 27 | Apr 10 | Mar 30 | Oct 14 | Oct 30 | Nov 13 |
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 Ansonia, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 18 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.
Ansonia planting FAQ
When is the last spring frost in Ansonia, CT?
Plan for the last spring frost in Ansonia around April 25 (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 Ansonia, CT?
Expect Ansonia's first fall frost near October 17 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Ansonia in?
Ansonia 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 Ansonia?
Ansonia has about 175 frost-free days — a moderate growing season — between the average last spring frost (April 25) and first fall frost (October 17).
When should I plant tomatoes in Ansonia?
For Ansonia, sow tomatoes indoors about February 28–March 14 and move the seedlings out around May 2, after the last spring frost.
Never miss a window in Ansonia
An email when it’s time to start seeds, transplant, and sow — timed to Ansonia’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Derby · 2 km
- Shelton · 7 km
- Orange · 8 km
- West Haven · 12 km
- New Haven · 13 km
- Milford · 13 km
- Trumbull Center · 15 km
- Naugatuck · 16 km
Frost dates recorded at ANSONIA 1 NE, 2 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 Ansonia, CT — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00060128. Retrieved from https://blissgarden.com/connecticut/ansonia.