When to Plant Onions in Vermont
Vermont gardeners get one real planting window for onions, and it opens in early spring, not fall.
Home & garden, state by state
Everything we have worked out for Vermont: what to plant and when, which varieties finish in time, the pests that actually turn up here, and the jobs that pay off month by month. We also cover the rest of the property, from lawns and soil to home care and energy, because a garden rarely stops at the vegetable bed.
The numbers first, because everything else follows from them. Measured at the weather station in Burlington, the last spring freeze runs April 30 to May 10 and the first fall freeze runs October 3 to October 13, USDA zones 3b-5b, 2,644 growing degree days in the year.
Garlic does well: 30.4 weeks below 40 °F, comfortably past the six it needs to form a proper head.
Elsewhere on the property in Vermont: the pests that turn up here.
Figures from NOAA's 1991-2020 climate normals. A state is not one climate: elevation, a large lake or the coast can move these dates by two weeks either way, so check your own county with the extension service before you spend money.
Vermont gardeners get one real planting window for onions, and it opens in early spring, not fall.
Vermont sits at a latitude where long summer daylight, not summer heat, decides whether an onion bulbs at all.
Vermont winters supply more cold than any spring bulb needs to bloom, so forcing indoors here isn’t about making up for a mild winter.
Yes, but the trick in Vermont isn’t waking bulbs up early. It’s keeping the pot itself from freezing solid.
Vermont’s apple stages, from dormancy to harvest, follow Burlington’s NOAA frost dates: April 30 to May 10 in spring, October 3 to 13 in fall.
Plant spring bulbs in Vermont from mid-September through late October in most valley locations, earlier at higher elevations and in the Northeast Kingdom.
In Burlington, Vermont’s reference point at 200 feet above sea level, water boils somewhere between 208°F and 212°F.
Vermont lawns need cool-season grass: Kentucky bluegrass, fine fescue, perennial ryegrass, tall fescue or rough bluegrass, chosen by sun, shade and traffic, then seeded in fall.
Vermont apple success depends on matching a tree’s winter hardiness and bloom timing to your local frost window, not a variety’s reputation.
Burlington’s coldest month bottoms out at an average low of 12.9°F, and that single number should decide how you buy, stack, and burn wood this winter.