4 planting zones in Connecticut with map

Connecticut has four USDA planting zones, ranging from 6a to 7b, according to the USDA’s latest plant hardiness zone map released in 2023.

Zone 6a, the coldest in Connecticut, is concentrated in the northwestern highlands, and zone 6b covers most of the state’s interior. Zones 7a and 7b are found along the southern coast, with 7b occupying a narrow strip along the immediate shoreline.

Find your specific USDA planting zone in Connecticut using one of two methods below: our ZIP code search tool or our interactive city-based Connecticut planting zone map.

Search Connecticut Plating Zones by ZipCode

Planting Zones Connecticut Map

Select you Connecticut city from the selection box below. Use top right corner button in mapview to select layers.

4 Planting zones in Connecticut

1. Zone 6a

Zone 6a, shown in dark blue color shade on our map above, covers the northwestern corner of Connecticut. With average annual minimum temperatures ranging from -10°F to -5°F (-23.3°C to -20.6°C), it the coldest region in the state. It includes the Litchfield Hills and parts of the Berkshire Mountains foothills. Cities in this zone are Torrington, Winsted, and Norfolk.

2. Zone 6b

Zone 6b, the teal colored areas on the map, dominates most of Connecticut’s interior. Having average annual minimum temperatures between -5°F and 0°F (-20.6°C to -17.8°C), this zone covers a large area of the state. It includes the Connecticut River Valley and extends from the central regions to the eastern border. Major cities in this zone are Hartford, New Britain, and Middletown.

3. Zone 7a

Zone 7a, the light green colored areas on our map above, primarily covers the coastal regions and southern portions of Connecticut. This zone experiences average annual minimum temperatures from 0°F to 5°F (-17.8°C to -15°C). It includes the Long Island Sound shoreline and extends slightly inland. Cities in this zone include New Haven, Bridgeport, and Stamford.

4. Zone 7b

Zone 7b, the yellow colored areas on our map, is the warmest zone in Connecticut and covers only a narrow strip of area along the southernmost coastline. With average annual minimum temperatures between 5°F and 10°F (-15°C to -12.2°C), this zone benefits from the moderating effect of Long Island Sound. While it’s a small area, it includes parts of coastal cities like Norwalk and specific neighborhoods such as Old Greenwich and Riverside.

Planting Zones in Connecticut with Cities

USDA hardiness zones for Connecticut cities, towns and counties (Data: Latest USDA (2023) release)

Planting Zones in Connecticut	Temp Range (°F)	Cities
6b	-5 to 0	Amston, Andover, Ansonia, Ashford, Avon, Ballouville, Baltic, Beacon Falls, Bethany, Bethel, Bloomfield, Bolton, Botsford, Bozrah, Bridgewater, Bristol, Broad Brook, Brookfield, Brooklyn, Canterbury, Central Village, Chaplin, Cheshire, Chester, Cobalt, Colchester, Columbia, Coventry, Cromwell, Danbury, Danielson, Dayville, Derby, Durham, East Berlin, East Glastonbury, East Granby, East Haddam, East Hampton, East Hartford, East Killingly, East Windsor, East Windsor Hill, Eastford, Easton, Ellington, Enfield, Farmington, Gaylordsville, Gilman, Glastonbury, Granby, Haddam, Hadlyme, Hamden, Hampton, Hanover, Hartford, Hawleyville, Hebron, Higganum, Jewett City, Kensington, Killingworth, Lebanon, Ledyard, Manchester, Mansfield Center, Mansfield Depot, Marion, Marlborough, Mashantucket, Meriden, Middle Haddam, Middlebury, Middlefield, Middletown, Milldale, Monroe, Moodus, Moosup, Naugatuck, New Britain, New Fairfield, New Milford, Newington, Newtown, North Franklin, North Haven, North Stonington, North Westchester, North Windham, Northford, Norwich, Oakdale, Oakville, Oneco, Oxford, Pequabuck, Plainfield, Plainville, Plantsville, Pomfret Center, Poquonock, Portland, Preston, Prospect, Putnam, Redding, Redding Center, Redding Ridge, Ridgefield, Rockfall, Rocky Hill, Rogers, Roxbury, Salem, Sandy Hook, Scotland, Seymour, Shelton, Sherman, Simsbury, Somers, Somersville, South Britain, South Glastonbury, South Willington, South Windham, South Windsor, South Woodstock, Southbury, Southington, Stafford Springs, Sterling, Stevenson, Storrs Mansfield, Suffield, Taftville, Tariffville, Terryville, Thompson, Tolland, Uncasville, Unionville, Vernon Rockville, Versailles, Voluntown, W Hartford, Wallingford, Waterbury, Watertown, Wauregan, Weatogue, West Simsbury, West Suffield, Wethersfield, Willimantic, Willington, Windham, Windsor, Windsor Locks, Wolcott, Woodbridge, Woodbury, Woodstock, Woodstock Valley, Yantic
6a	-10 to -5	Bantam, Bethlehem, Burlington, Canaan, Canton, Canton Center, Colebrook, Collinsville, Cornwall, Cornwall Bridge, East Canaan, East Hartland, East Woodstock, Fabyan, Falls Village, Goshen, Grosvenor Dale, Harwinton, Kent, Lakeside, Lakeville, Litchfield, Morris, New Hartford, New Preston Marble Dale, Norfolk, North Canton, North Granby, North Grosvenordale, Northfield, Pine Meadow, Pleasant Valley, Plymouth, Quinebaug, Riverton, Salisbury, Sharon, South Kent, Stafford, Staffordville, Taconic, Thomaston, Torrington, Washington, Washington Depot, West Cornwall, West Granby, West Hartland, Winchester Center, Winsted
7a	0 to 5	Branford, Bridgeport, Centerbrook, Clinton, Cos Cob, Darien, Deep River, East Haven, East Lyme, Essex, Fairfield, Gales Ferry, Georgetown, Greens Farms, Greenwich, Groton, Guilford, Hamden, Ivoryton, Madison, Milford, Mystic, New Canaan, New Haven, New London, Niantic, North Branford, Norwalk, Old Lyme, Old Mystic, Old Saybrook, Orange, Pawcatuck, Quaker Hill, South Lyme, Southport, Stamford, Stonington, Stratford, Trumbull, Waterford, West Haven, West Mystic, Westbrook, Weston, Westport, Wethersfield, Wilton
7b	5 to 10	Norwalk, Old Greenwich, Riverside

How Connecticut’s geography influence its planting zones?

Connecticut’s geography factor like elevation, coastal influence and lattitude directly influences its USDA growing zones:

1. Elevation: Higher elevations in the northwest (Litchfield Hills) create cooler zones (6a), while lower elevations in the interior are mostly zone 6b.
2. Coastal influence: Long Island Sound moderates temperatures along the southern coast, resulting in warmer zones (7a and 7b).
3. Latitude: Generally, southern parts of the state are warmer than northern areas.