FrostCal

When to Plant Zucchini in Illinois

In a typical Illinois location, start seeds indoors Mar 30 – Apr 6, then sow outdoors Apr 27 – May 11, then transplant outdoors Apr 27 – May 4. Across the state, the outdoor planting window starts as early as Apr 8 in Granite City and as late as May 8 in Roscoe.

Method Direct sow
Days to maturity 45–55 days

Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start.

Zucchini Planting Dates by City

CityStart indoorsDirect sowTransplant
ChicagoMar 20 – Mar 27Apr 17 – May 1Apr 17 – Apr 24
AuroraMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
RockfordApr 3 – Apr 10May 1 – May 15May 1 – May 8
JolietMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
NapervilleApr 7 – Apr 14May 5 – May 19May 5 – May 12
PeoriaMar 26 – Apr 2Apr 23 – May 7Apr 23 – Apr 30
SpringfieldMar 25 – Apr 1Apr 22 – May 6Apr 22 – Apr 29
North PeoriaMar 26 – Apr 2Apr 23 – May 7Apr 23 – Apr 30
ElginApr 5 – Apr 12May 3 – May 17May 3 – May 10
WaukeganApr 9 – Apr 16May 7 – May 21May 7 – May 14
ChampaignMar 25 – Apr 1Apr 22 – May 6Apr 22 – Apr 29
CiceroMar 21 – Mar 28Apr 18 – May 2Apr 18 – Apr 25
BloomingtonMar 31 – Apr 7Apr 28 – May 12Apr 28 – May 5
Arlington HeightsMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
EvanstonApr 5 – Apr 12May 3 – May 17May 3 – May 10
SchaumburgApr 9 – Apr 16May 7 – May 21May 7 – May 14
BolingbrookMar 30 – Apr 6Apr 27 – May 11Apr 27 – May 4
DecaturMar 24 – Mar 31Apr 21 – May 5Apr 21 – Apr 28
PalatineApr 4 – Apr 11May 2 – May 16May 2 – May 9
SkokieApr 5 – Apr 12May 3 – May 17May 3 – May 10
Des PlainesMar 26 – Apr 2Apr 23 – May 7Apr 23 – Apr 30
Orland ParkMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
Tinley ParkApr 2 – Apr 9Apr 30 – May 14Apr 30 – May 7
Oak LawnMar 20 – Mar 27Apr 17 – May 1Apr 17 – Apr 24
BerwynMar 21 – Mar 28Apr 18 – May 2Apr 18 – Apr 25
Mount ProspectMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
NormalApr 4 – Apr 11May 2 – May 16May 2 – May 9
WheatonApr 7 – Apr 14May 5 – May 19May 5 – May 12
Oak ParkMar 21 – Mar 28Apr 18 – May 2Apr 18 – Apr 25
Hoffman EstatesApr 9 – Apr 16May 7 – May 21May 7 – May 14

Showing the 30 most populous of 242 Illinois cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Illinois cities.

Frequently Asked Questions

When should I plant zucchini in Illinois?

In a typical Illinois location, start seeds indoors Mar 30 – Apr 6, then sow outdoors Apr 27 – May 11, then transplant outdoors Apr 27 – May 4. Across the state, the outdoor planting window starts as early as Apr 8 in Granite City and as late as May 8 in Roscoe.

When is the last frost in Illinois?

The average last spring frost in Illinois ranges from April 1 in Granite City to May 1 in Roscoe, based on NOAA 1991–2020 climate normals.

How long do zucchini take to grow?

Zucchini typically take 45–55 days from planting to harvest. Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start.

Other Crops in Illinois

When to plant zucchini in other states

Related Guides