Regional guide

Illinois Three-Region Vegetable Garden

An Illinois vegetable guide for Northern, Central, and Southern planting-date columns, frost-free ranges, and seasonal crop timing.

Climate signals

• Illinois Extension ties planting dates to first and last frost dates, crop maturity, and whether a crop is cool-season or warm-season.
• Regional spring frost-free median dates are Northern Illinois April 8-29, Central Illinois April 8-15, and Southern Illinois April 1-8.
• Southern Illinois can generally start crops about two weeks earlier than Central Illinois and harvest about two weeks longer, while Northern Illinois has a shorter season and can plant about two weeks later.
• Illinois spans hardiness zones 5a through 7b, but the source notes that zones mostly apply to perennial landscape plants because most vegetable crops are annuals.

Planning notes

• Use the Northern, Central, and Southern Illinois columns instead of one statewide date; around Chicago, refine timing with the source's frost-date maps or a local Extension office.
• Use lettuce's two-season rows as a cool-season anchor: Northern Illinois April 15 to May 15 and July 15 to Sept. 15, Central Illinois April 1 to 30 and July 1 to Aug. 31, and Southern Illinois March 15 to April 15 and June 15 to Aug. 15.
• Use tomato transplant timing as a warm-season anchor: Northern Illinois May 24 to June 15, Central Illinois May 10 to June 1, and Southern Illinois April 28 to May 15.
• Use bush bean succession windows where the chart lists two ranges: Northern Illinois May 24 to June 30 or July 30 to Aug. 14, Central Illinois May 10 to June 15 or July 15 to 30, and Southern Illinois April 26 to June 1 or July 1 to July 15.
• Use fall-capable cool-season rows for spinach, radish, mustard, turnip, broccoli, cabbage, kale, beets, carrots, and chard, then confirm local seed packet maturity and frost risk.

Catalog crop examples

These catalog entries match crops covered by the regional timing source; variety-specific details remain tied to each seed entry's own source.

• Black Seeded Simpson Lettuce Vegetable · Cool · 45 days
• Bloomsdale Spinach Vegetable · Cool · 42 days
• French Breakfast Radish Vegetable · Cool · 28 days
• Southern Giant Curled Mustard Vegetable · Cool · 45 days
• Purple Top White Globe Turnip Vegetable · Cool · 55 days
• Detroit Dark Red Beet Vegetable · Cool · 58 days
• Waltham 29 Broccoli Vegetable · Cool · 74 days
• Golden Acre Cabbage Vegetable · Cool · 64 days
• Danvers 126 Carrot Vegetable · Shoulder · 70 days
• Lacinato Kale Vegetable · Cool · 60 days
• Bright Lights Swiss Chard Vegetable · Shoulder · 55 days
• Early White Vienna Kohlrabi Vegetable · Cool · 55 days
• Provider Bush Bean Vegetable · Warm · 50 days
• Golden Bantam Sweet Corn Vegetable · Warm · 80 days
• Marketmore 76 Cucumber Vegetable · Warm · 58 days
• Black Beauty Eggplant Vegetable · Warm · 80 days
• California Wonder Pepper Vegetable · Warm · 72 days
• Small Sugar Pumpkin Vegetable · Warm · 100 days
• Waltham Butternut Squash Vegetable · Warm · 95 days
• Roma Tomato Vegetable · Warm · 76 days
• Sugar Baby Watermelon Vegetable · Warm · 80 days

Related regional guides

• Chicago Area Illinois Vegetable Planting Guide Illinois Extension guide for Chicago-area gardeners using Northern Illinois planting windows with an urban heat caveat against Central Illinois dates.
• McHenry County Illinois Planting Guide Illinois Extension McHenry County guide for seven vegetable planting windows, transplant labels, and fall harvest timing.

Source: Illinois Extension when to plant