FrostCal

When to Plant Zucchini in Iowa

In a typical Iowa location, start seeds indoors Mar 31 – Apr 7, then sow outdoors Apr 28 – May 12, then transplant outdoors Apr 28 – May 5. Across the state, the outdoor planting window starts as early as Apr 17 in Keokuk and as late as May 10 in Grinnell.

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
Des MoinesMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
Cedar RapidsApr 7 – Apr 14May 5 – May 19May 5 – May 12
DavenportMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
Sioux CityApr 8 – Apr 15May 6 – May 20May 6 – May 13
Iowa CityMar 31 – Apr 7Apr 28 – May 12Apr 28 – May 5
WaterlooApr 6 – Apr 13May 4 – May 18May 4 – May 11
AmesApr 5 – Apr 12May 3 – May 17May 3 – May 10
West Des MoinesMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
Council BluffsMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
DubuqueMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
AnkenyApr 2 – Apr 9Apr 30 – May 14Apr 30 – May 7
UrbandaleMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
Cedar FallsApr 6 – Apr 13May 4 – May 18May 4 – May 11
MarionApr 7 – Apr 14May 5 – May 19May 5 – May 12
BettendorfMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
MarshalltownApr 7 – Apr 14May 5 – May 19May 5 – May 12
Mason CityApr 8 – Apr 15May 6 – May 20May 6 – May 13
ClintonMar 23 – Mar 30Apr 20 – May 4Apr 20 – Apr 27
BurlingtonMar 25 – Apr 1Apr 22 – May 6Apr 22 – Apr 29
Fort DodgeApr 7 – Apr 14May 5 – May 19May 5 – May 12
OttumwaApr 2 – Apr 9Apr 30 – May 14Apr 30 – May 7
MuscatineMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
JohnstonMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
CoralvilleMar 31 – Apr 7Apr 28 – May 12Apr 28 – May 5
WaukeeMar 29 – Apr 5Apr 26 – May 10Apr 26 – May 3
AltoonaMar 31 – Apr 7Apr 28 – May 12Apr 28 – May 5
North LibertyMar 31 – Apr 7Apr 28 – May 12Apr 28 – May 5
IndianolaApr 3 – Apr 10May 1 – May 15May 1 – May 8
CliveMar 28 – Apr 4Apr 25 – May 9Apr 25 – May 2
NewtonApr 1 – Apr 8Apr 29 – May 13Apr 29 – May 6

Showing the 30 most populous of 45 Iowa cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Iowa cities.

Frequently Asked Questions

When should I plant zucchini in Iowa?

In a typical Iowa location, start seeds indoors Mar 31 – Apr 7, then sow outdoors Apr 28 – May 12, then transplant outdoors Apr 28 – May 5. Across the state, the outdoor planting window starts as early as Apr 17 in Keokuk and as late as May 10 in Grinnell.

When is the last frost in Iowa?

The average last spring frost in Iowa ranges from April 10 in Keokuk to May 3 in Grinnell, 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 Iowa

When to plant zucchini in other states

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