Vermont Frost Dates & Growing Season Guide
Vermont (VT) spans USDA hardiness zones 4b, 5a, 5b, with growing seasons ranging from 130 days in Montpelier to 155 days in Brattleboro. The average growing season across the state is approximately 144 days.
Vermont City Frost Dates
The table below shows the average last spring frost date, first fall frost date, growing season length, and USDA hardiness zone for each city. Click a city name for detailed planting calendars and zone information.
| City | Last Spring Frost | First Fall Frost | Growing Season | Zone | Min Temp |
|---|---|---|---|---|---|
| Burlington | May 5 | October 3 | 151 days | 5a | -20°F |
| Montpelier | May 15 | September 22 | 130 days | 4b | -25°F |
| Rutland | May 10 | September 28 | 141 days | 5a | -20°F |
| Brattleboro | May 3 | October 5 | 155 days | 5b | -15°F |
Planting Windows for Vermont
Based on average frost dates, here are the recommended planting windows for each city. The indoor seed start date is approximately seven weeks before the last spring frost. Transplanting should occur about two weeks after the last frost. The last direct sow date for fall crops is ten weeks before the first fall frost.
| City | Start Seeds Indoors | Transplant After | Last Direct Sow |
|---|---|---|---|
| Burlington | March 17 | May 19 | July 25 |
| Montpelier | March 27 | May 29 | July 14 |
| Rutland | March 22 | May 24 | July 20 |
| Brattleboro | March 15 | May 17 | July 27 |
Gardening in Vermont
Vermont's northern climate and mountainous terrain create a gardening environment that rewards resilience and planning. Growing seasons range from 130 days in Montpelier to 155 days in the southern Connecticut River Valley. The state's reputation for cold winters is balanced by fertile glacial soils and a tradition of self-sufficient food production. Vermont gardeners excel at root crops, brassicas, greens, and cold-hardy herbs. The state's cool nights produce exceptional flavor in crops like carrots, kale, and lettuce. Season extension with hoop houses and cold frames is widely practiced. Many Vermont farms and gardens use living mulches and cover crops to maintain soil health through the long winter. Apple cider, maple syrup, and artisan cheese reflect the state's food culture.
Understanding Vermont's Hardiness Zones
Vermont includes USDA hardiness zones 4b, 5a, 5b. These zones indicate the average annual extreme minimum winter temperature for each area, which determines which perennial plants, trees, and shrubs can survive winter without protection. When purchasing trees, shrubs, or perennial flowers, always check that the plant is rated for your hardiness zone or a lower (colder) zone number.
Zone 4b
-25°F to -20°F
Central Midwest and mountain valleys; wide vegetable gardening
Tips for Using Vermont Frost Dates
These frost dates represent long-term averages and should be treated as guidelines rather than guarantees. In any given year, the actual last spring frost or first fall frost may arrive one to three weeks earlier or later than the average. Factors that affect your specific location include elevation above the city center, proximity to water, slope direction, and whether you are in an urban or rural area. South-facing slopes and areas near large pavement or building masses tend to be warmer than surrounding open land. Low-lying valleys and exposed hilltops are often colder than mid-slope positions.
To protect against late spring frosts, keep row cover fabric, old bed sheets, or frost blankets on hand. Monitor your local weather forecast daily as the average frost date approaches. When frost is predicted after you have transplanted, covering plants in the late afternoon traps ground heat and can protect against temperatures down to about 28 degrees Fahrenheit. For fall season extension, the same covers protect mature plants from early frosts, often buying several additional weeks of harvest.