When to plant Summer squash (zucchini) in Michigan

In spring, from May 1 – 30 in Adrian to May 20 – June 15 in Cadillac.

In fall, June 1 – July 15.

USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.

Summer squash planting dates by place in Michigan
PlaceSpringFall
AdrianMay 1 – 30June 1 – July 15
Allen ParkMay 1 – 30June 1 – July 15
AlpenaMay 1 – 30June 1 – July 20
Ann ArborMay 1 – 30June 1 – July 15
Auburn HillsMay 1 – 30June 1 – July 20
Battle CreekMay 1 – 30June 1 – July 20
Bay CityMay 1 – 30June 1 – July 20
BerkleyMay 1 – 30June 1 – July 20
Beverly HillsMay 1 – 30June 1 – July 20
BirminghamMay 1 – 30June 1 – July 20
BurtonMay 10 – June 10June 1 – July 1
CadillacMay 20 – June 15June 1 – July 1
ClawsonMay 1 – 30June 1 – July 20
ColdwaterMay 1 – 30June 1 – July 15
DearbornMay 1 – 30June 1 – July 15
Dearborn HeightsMay 1 – 30June 1 – July 15
DetroitMay 1 – 30June 1 – July 20
East Grand RapidsMay 10 – June 10June 1 – July 15
East LansingMay 1 – 30June 1 – July 20
EastpointeMay 1 – 30June 1 – July 20
EscanabaMay 10 – June 10June 1 – July 15
FarmingtonMay 1 – 30June 1 – July 20
Farmington HillsMay 1 – 30June 1 – July 20
FentonMay 1 – 30June 1 – July 15
FerndaleMay 1 – June 15June 1 – Aug 1
Flat RockMay 1 – 30June 1 – July 20
FlintMay 1 – 30June 1 – July 15
FraserMay 1 – 30June 1 – July 20
Garden CityMay 1 – 30June 1 – July 15
Grand HavenMay 1 – 30June 1 – July 20
Grand RapidsMay 10 – June 10June 1 – July 15
GrandvilleMay 10 – June 10June 1 – July 15
Grosse Pointe ParkMay 1 – 30June 1 – July 20
Grosse Pointe WoodsMay 1 – 30June 1 – July 20
HamtramckMay 1 – June 15June 1 – Aug 1
Harper WoodsMay 1 – 30June 1 – July 20
Hazel ParkMay 1 – June 15June 1 – Aug 1
HollandMay 1 – 30June 1 – July 20
InksterMay 1 – June 15June 1 – Aug 1
IoniaMay 1 – 30June 1 – July 15
JacksonMay 1 – 30June 1 – July 15
KalamazooMay 1 – 30June 1 – July 20
KentwoodMay 1 – 30June 1 – July 15
LansingMay 1 – 30June 1 – July 15
Lincoln ParkMay 1 – 30June 1 – July 15
LivoniaMay 1 – 30June 1 – July 20
Madison HeightsMay 1 – June 15June 1 – Aug 1
MarquetteMay 10 – June 10June 1 – July 20
MelvindaleMay 1 – 30June 1 – July 15
MidlandMay 1 – 30June 1 – July 20
MonroeMay 1 – June 15June 1 – July 20
Mount ClemensMay 1 – 30June 1 – July 20
Mount PleasantMay 1 – 30June 1 – July 20
MuskegonMay 1 – 30June 1 – July 20
New BaltimoreMay 1 – 30June 1 – July 20
NilesMay 1 – 30June 1 – July 20
Norton ShoresMay 1 – 30June 1 – July 20
NoviMay 1 – 30June 1 – July 20
Oak ParkMay 1 – 30June 1 – July 20
OwossoMay 1 – 30June 1 – July 15
PontiacMay 1 – 30June 1 – July 20
Port HuronMay 1 – June 15June 1 – Aug 1
PortageMay 1 – 30June 1 – July 20
RiverviewMay 1 – June 15June 1 – Aug 1
RochesterMay 1 – 30June 1 – July 20
Rochester HillsMay 1 – 30June 1 – July 20
RomulusMay 1 – June 15June 1 – Aug 1
RosevilleMay 1 – 30June 1 – July 20
Royal OakMay 1 – June 15June 1 – Aug 1
SaginawMay 1 – 30June 1 – July 20
Sault Ste. MarieMay 10 – June 10June 1 – July 15
South LyonMay 1 – 30June 1 – July 15
SouthfieldMay 1 – 30June 1 – July 20
SouthgateMay 1 – June 15June 1 – Aug 1
St. Clair ShoresMay 1 – 30June 1 – July 20
Sterling HeightsMay 1 – 30June 1 – July 20
SturgisMay 1 – 30June 1 – July 20
TaylorMay 1 – June 15June 1 – Aug 1
Traverse CityMay 10 – June 10June 1 – July 20
TrentonMay 1 – June 15June 1 – Aug 1
TroyMay 1 – 30June 1 – July 20
WalkerMay 10 – June 10June 1 – July 15
WarrenMay 1 – June 15June 1 – Aug 1
WayneMay 1 – June 15June 1 – Aug 1
WestlandMay 1 – June 15June 1 – Aug 1
WixomMay 10 – June 10June 1 – July 15
WoodhavenMay 1 – June 15June 1 – Aug 1
WyandotteMay 1 – 30June 1 – July 15
WyomingMay 10 – June 10June 1 – July 15
YpsilantiMay 1 – 30June 1 – July 15

Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for summer squash.