Garden Pests in Illinois: What Shows Up, When, and How to Stop It
A season-by-season look at the eight pests Illinois Extension flags most often, how to identify them, and which controls actually work in home gardens.
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.
Illinois Lawn Care: What to Plant and When to Feed It
Illinois lawns need cool-season grass species, and this guide gives the seeding window, feeding rates and mowing heights that fit the state’s climate.
Garlic Varieties That Suit Illinois Winters
Illinois garlic growers get better bulbs from cold-hardy hardnecks timed to NOAA’s Chicago-area first fall freeze window.
When to Plant Garlic in Illinois: Counting Back From the First Frost
Illinois garlic goes in early to mid-October, timed four to six weeks before NOAA’s Chicago-area first frost window, with adjustments for your own county.
Growing Garlic in Illinois: Planting Dates, Varieties and Winter Cold
Illinois growers get enough winter cold for hardneck garlic to divide well, and this guide gives the fall planting window, variety picks and curing tips for the state’s humid summers.
Tomato Varieties That Ripen in Time in Illinois
Eight cataloged tomato varieties compared against Illinois’s frost window, from 55-day cherry tomatoes to 85-day heirlooms, so you can pick what actually ripens.
Tomato Pests in Illinois: Which Ones Actually Show Up Here
A season-by-season identification guide to the tomato pests confirmed in Illinois gardens, with what to look for and what controls each.
Tomato Planting Dates in Illinois: Counting Back From Your Frost Window
Learn how to use NOAA’s Chicago-area frost window to work out your own tomato transplant and harvest dates in Illinois.
Growing Tomatoes in Illinois: Planting Dates, Varieties and Local Pests
Illinois tomato planting dates depend on your area’s last frost, with Chicago’s window as a reference point and disease-resistant varieties suited to the state’s variable season.