When to plant Summer squash (zucchini) in Wisconsin

In spring, from May 1 – 30 in Allouez to May 10 – June 10 in Wisconsin Rapids.

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 Wisconsin
PlaceSpringFall
AllouezMay 1 – 30June 1 – July 15
AppletonMay 1 – 30June 1 – July 15
AshwaubenonMay 1 – 30June 1 – July 15
BarabooMay 1 – 30June 1 – July 1
Beaver DamMay 1 – 30June 1 – July 15
BellevueMay 1 – 30June 1 – July 15
BeloitMay 1 – 30June 1 – July 15
BrookfieldMay 1 – 30June 1 – July 15
Brown DeerMay 1 – 30June 1 – July 20
BurlingtonMay 1 – 30June 1 – July 15
CaledoniaMay 1 – June 15June 1 – July 20
CedarburgMay 1 – June 15June 1 – July 20
Chippewa FallsMay 10 – June 10June 1 – July 1
CudahyMay 1 – June 15June 1 – Aug 1
De PereMay 1 – 30June 1 – July 15
DeForestMay 1 – 30June 1 – July 15
Eau ClaireMay 1 – June 15June 1 – July 15
ElkhornMay 1 – 30June 1 – July 15
FitchburgMay 1 – 30June 1 – July 15
Fond du LacMay 1 – 30June 1 – July 20
Fort AtkinsonMay 1 – 30June 1 – July 15
Fox CrossingMay 1 – 30June 1 – July 15
FranklinMay 1 – 30June 1 – July 15
GermantownMay 10 – June 10June 1 – July 15
GlendaleMay 1 – 30June 1 – July 20
GraftonMay 1 – June 15June 1 – July 20
Green BayMay 10 – June 10June 1 – July 15
GreendaleMay 1 – 30June 1 – July 15
GreenfieldMay 1 – 30June 1 – July 15
GreenvilleMay 1 – 30June 1 – July 15
HarrisonMay 1 – 30June 1 – July 15
HartfordMay 10 – June 10June 1 – July 1
HartlandMay 1 – 30June 1 – July 15
HobartMay 1 – 30June 1 – July 15
HolmenMay 1 – June 15June 1 – July 20
HowardMay 10 – June 10June 1 – July 15
HudsonMay 1 – June 15June 1 – July 20
JanesvilleMay 1 – 30June 1 – July 15
KaukaunaMay 1 – 30June 1 – July 15
KenoshaMay 1 – 30June 1 – July 20
La CrosseMay 1 – 30June 1 – July 15
LisbonMay 1 – 30June 1 – July 20
Little ChuteMay 1 – 30June 1 – July 15
MadisonMay 1 – 30June 1 – July 15
ManitowocMay 1 – 30June 1 – July 20
MarinetteMay 1 – 30June 1 – July 15
MarshfieldMay 1 – 30June 1 – July 1
MenashaMay 1 – 30June 1 – July 15
Menomonee FallsMay 10 – June 10June 1 – July 15
MenomonieMay 10 – June 10June 1 – July 1
MequonMay 10 – June 10June 1 – July 15
MiddletonMay 1 – 30June 1 – July 15
MilwaukeeMay 1 – 30June 1 – July 20
MonroeMay 1 – 30June 1 – July 15
Mount PleasantMay 1 – June 15June 1 – July 20
MuskegoMay 1 – 30June 1 – July 15
NeenahMay 1 – 30June 1 – July 15
New BerlinMay 1 – 30June 1 – July 15
New RichmondMay 1 – June 15June 1 – July 20
Oak CreekMay 1 – June 15June 1 – Aug 1
OconomowocMay 1 – 30June 1 – July 15
OnalaskaMay 1 – June 15June 1 – July 20
OregonMay 1 – 30June 1 – July 15
OshkoshMay 1 – June 15June 1 – July 20
PewaukeeMay 1 – 30June 1 – July 15
PlattevilleMay 1 – 30June 1 – July 15
Pleasant PrairieMay 1 – June 15June 1 – Aug 1
PloverMay 1 – 30June 1 – July 15
Port WashingtonMay 1 – 30June 1 – July 20
RacineMay 1 – June 15June 1 – July 20
ReedsburgMay 1 – 30June 1 – July 15
RichfieldMay 1 – 30June 1 – July 20
River FallsMay 10 – June 10June 1 – July 1
Salem LakesMay 1 – 30June 1 – July 15
SheboyganMay 1 – June 15June 1 – July 20
ShorewoodMay 1 – 30June 1 – July 20
South MilwaukeeMay 1 – June 15June 1 – Aug 1
Stevens PointMay 1 – 30June 1 – July 15
StoughtonMay 1 – 30June 1 – July 15
SuamicoMay 10 – June 10June 1 – July 15
Sun PrairieMay 1 – 30June 1 – July 15
SuperiorMay 10 – June 10June 1 – July 15
SussexMay 1 – 30June 1 – July 20
Two RiversMay 1 – 30June 1 – July 20
VeronaMay 1 – 30June 1 – July 15
WatertownMay 1 – 30June 1 – July 15
WaukeshaMay 1 – 30June 1 – July 15
WaunakeeMay 1 – 30June 1 – July 15
WaupunMay 1 – 30June 1 – July 15
WausauMay 10 – June 10June 1 – July 1
WauwatosaMay 1 – 30June 1 – July 20
West AllisMay 1 – 30June 1 – July 20
West BendMay 1 – 30June 1 – July 15
WestonMay 10 – June 10June 1 – July 1
Whitefish BayMay 1 – 30June 1 – July 20
WhitewaterMay 1 – 30June 1 – July 15
WindsorMay 1 – 30June 1 – July 15
Wisconsin RapidsMay 10 – June 10June 1 – July 1

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.