When to Plant Acorn Squash in Illinois

Growing Acorn Squash in Illinois: Complete Guide

Acorn Squash (Cucurbita pepo) is a warm-season crop that needs a head start indoors before Illinois's last frost. Depending on your zone, Illinois gardeners start seeds indoors between March 13, 2027 (Zone 7a) and April 12, 2027 (Zone 5a), then move transplants outside once their zone's last frost has passed — the zone table above has your exact dates.

Because Illinois stretches across 5 USDA hardiness zones (5a, 5b, 6a, 6b, 7a), planting windows can shift by as much as six to eight weeks from one end of the state to the other. Gardeners in the warmer southern zones can start earlier, while those in cooler northern zones should wait until the zone table above shows their last frost has passed.

With 85 days to maturity, Acorn Squash needs the indoor head start that Illinois's growing season requires. Starting indoors ensures you have strong transplants ready the moment outdoor conditions are right.

Acorn Squash requires full sun (6-8 hours) and regular (1 inch/week) moisture. Midwest growing seasons are compressed between late spring frosts and fall cold snaps, so timing transplants precisely pays off.

For the most precise planting dates tailored to your exact location, enter your ZIP code on our planting calendar or use the zone table above to find the schedule for your area of Illinois.