FrostCal

When to Plant Cosmos in Indiana

In a typical Indiana location, start seeds indoors Mar 25 – Apr 1, then sow outdoors Apr 29 – May 13, then transplant outdoors Apr 29 – May 6. Across the state, the outdoor planting window starts as early as Apr 5 in Evansville and as late as May 9 in Auburn.

Method Direct sow
Days to maturity 60–90 days

Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.

Cosmos Planting Dates by City

CityStart indoorsDirect sowTransplant
IndianapolisMar 23 – Mar 30Apr 27 – May 11Apr 27 – May 4
Fort WayneMar 27 – Apr 3May 1 – May 15May 1 – May 8
EvansvilleMar 1 – Mar 8Apr 5 – Apr 19Apr 5 – Apr 12
South BendMar 26 – Apr 2Apr 30 – May 14Apr 30 – May 7
CarmelMar 24 – Mar 31Apr 28 – May 12Apr 28 – May 5
BloomingtonMar 18 – Mar 25Apr 22 – May 6Apr 22 – Apr 29
HammondMar 26 – Apr 2Apr 30 – May 14Apr 30 – May 7
GaryMar 25 – Apr 1Apr 29 – May 13Apr 29 – May 6
FishersMar 24 – Mar 31Apr 28 – May 12Apr 28 – May 5
LafayetteMar 29 – Apr 5May 3 – May 17May 3 – May 10
MuncieMar 19 – Mar 26Apr 23 – May 7Apr 23 – Apr 30
Terre HauteMar 18 – Mar 25Apr 22 – May 6Apr 22 – Apr 29
NoblesvilleMar 24 – Mar 31Apr 28 – May 12Apr 28 – May 5
KokomoMar 30 – Apr 6May 4 – May 18May 4 – May 11
GreenwoodMar 23 – Mar 30Apr 27 – May 11Apr 27 – May 4
AndersonMar 22 – Mar 29Apr 26 – May 10Apr 26 – May 3
ElkhartMar 29 – Apr 5May 3 – May 17May 3 – May 10
MishawakaMar 26 – Apr 2Apr 30 – May 14Apr 30 – May 7
LawrenceMar 21 – Mar 28Apr 25 – May 9Apr 25 – May 2
JeffersonvilleMar 3 – Mar 10Apr 7 – Apr 21Apr 7 – Apr 14
ColumbusMar 14 – Mar 21Apr 18 – May 2Apr 18 – Apr 25
West LafayetteMar 29 – Apr 5May 3 – May 17May 3 – May 10
PortageMar 25 – Apr 1Apr 29 – May 13Apr 29 – May 6
WestfieldMar 24 – Mar 31Apr 28 – May 12Apr 28 – May 5
New AlbanyMar 3 – Mar 10Apr 7 – Apr 21Apr 7 – Apr 14
RichmondMar 27 – Apr 3May 1 – May 15May 1 – May 8
MerrillvilleMar 25 – Apr 1Apr 29 – May 13Apr 29 – May 6
GoshenMar 29 – Apr 5May 3 – May 17May 3 – May 10
ValparaisoMar 25 – Apr 1Apr 29 – May 13Apr 29 – May 6
Michigan CityMar 22 – Mar 29Apr 26 – May 10Apr 26 – May 3

Showing the 30 most populous of 88 Indiana cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Indiana cities.

Frequently Asked Questions

When should I plant cosmos in Indiana?

In a typical Indiana location, start seeds indoors Mar 25 – Apr 1, then sow outdoors Apr 29 – May 13, then transplant outdoors Apr 29 – May 6. Across the state, the outdoor planting window starts as early as Apr 5 in Evansville and as late as May 9 in Auburn.

When is the last frost in Indiana?

The average last spring frost in Indiana ranges from March 29 in Evansville to May 2 in Auburn, based on NOAA 1991–2020 climate normals.

How long do cosmos take to grow?

Cosmos typically take 60–90 days from planting to harvest. Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.

Other Crops in Indiana

When to plant cosmos in other states

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