FrostCal

When to Plant Zinnias in South Dakota

In a typical South Dakota location, start seeds indoors Apr 8 – Apr 15, then sow outdoors May 13 – May 27, then transplant outdoors May 13 – May 20. Across the state, the outdoor planting window starts as early as May 3 in Tea and as late as May 19 in Ellsworth Air Force Base.

Method Direct sow
Days to maturity 60–70 days

Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.

Zinnias Planting Dates by City

CityStart indoorsDirect sowTransplant
Sioux FallsApr 3 – Apr 10May 8 – May 22May 8 – May 15
Rapid CityApr 5 – Apr 12May 10 – May 24May 10 – May 17
AberdeenApr 10 – Apr 17May 15 – May 29May 15 – May 22
BrookingsApr 8 – Apr 15May 13 – May 27May 13 – May 20
WatertownApr 9 – Apr 16May 14 – May 28May 14 – May 21
MitchellApr 4 – Apr 11May 9 – May 23May 9 – May 16
YanktonMar 30 – Apr 6May 4 – May 18May 4 – May 11
PierreApr 8 – Apr 15May 13 – May 27May 13 – May 20
HuronApr 8 – Apr 15May 13 – May 27May 13 – May 20
SpearfishApr 14 – Apr 21May 19 – Jun 2May 19 – May 26
VermillionApr 5 – Apr 12May 10 – May 24May 10 – May 17
BrandonApr 3 – Apr 10May 8 – May 22May 8 – May 15
Box ElderApr 14 – Apr 21May 19 – Jun 2May 19 – May 26
Rapid ValleyApr 5 – Apr 12May 10 – May 24May 10 – May 17
Ellsworth Air Force BaseApr 14 – Apr 21May 19 – Jun 2May 19 – May 26
MadisonApr 7 – Apr 14May 12 – May 26May 12 – May 19
SturgisApr 10 – Apr 17May 15 – May 29May 15 – May 22
Belle FourcheApr 12 – Apr 19May 17 – May 31May 17 – May 24
HarrisburgApr 4 – Apr 11May 9 – May 23May 9 – May 16
TeaMar 29 – Apr 5May 3 – May 17May 3 – May 10

Showing the 20 most populous of 20 South Dakota cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all South Dakota cities.

Frequently Asked Questions

When should I plant zinnias in South Dakota?

In a typical South Dakota location, start seeds indoors Apr 8 – Apr 15, then sow outdoors May 13 – May 27, then transplant outdoors May 13 – May 20. Across the state, the outdoor planting window starts as early as May 3 in Tea and as late as May 19 in Ellsworth Air Force Base.

When is the last frost in South Dakota?

The average last spring frost in South Dakota ranges from April 26 in Tea to May 12 in Ellsworth Air Force Base, based on NOAA 1991–2020 climate normals.

How long do zinnias take to grow?

Zinnias typically take 60–70 days from planting to harvest. Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.

Other Crops in South Dakota

When to plant zinnias in other states

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