Gardening in Illinois

Everything we have worked out for Illinois: 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 Chicago, the last spring freeze runs April 11 to April 22 and the first fall freeze runs October 24 to November 3, USDA zones 5a-7b, 3,274 growing degree days in the year.

Garlic does well: 26.1 weeks below 40 °F, comfortably past the six it needs to form a proper head.

Elsewhere on the property in Illinois: 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.