GreenlyWhen to plant cucumber in Chicago
In Chicago, cucumber: sow seedlings around 26 March for the greenhouse and around 16 April for open ground; plant into a greenhouse around 7 May; plant out into open ground around 28 May.
Last spring frost around 18 April, first autumn frost around 6 November. Frost-free days: 202 days.
The dates follow the Greenly calendar: open ground a week after the last frost once the soil is warm enough for the crop, frost-hardy crops three weeks before it, an unheated greenhouse three weeks earlier, seedlings sown so they are ready on the day. In a cold year allow a week or two more.