FrostCal

When to Plant Cosmos in Vermont

In a typical Vermont location, start seeds indoors Apr 11 – Apr 18, then sow outdoors May 16 – May 30, then transplant outdoors May 16 – May 23. Across the state, the outdoor planting window starts as early as May 6 in Burlington and as late as May 27 in Morristown.

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
BurlingtonApr 1 – Apr 8May 6 – May 20May 6 – May 13
South BurlingtonApr 1 – Apr 8May 6 – May 20May 6 – May 13
ColchesterApr 4 – Apr 11May 9 – May 23May 9 – May 16
RutlandApr 17 – Apr 24May 22 – Jun 5May 22 – May 29
Essex JunctionApr 4 – Apr 11May 9 – May 23May 9 – May 16
HartfordApr 11 – Apr 18May 16 – May 30May 16 – May 23
BenningtonApr 13 – Apr 20May 18 – Jun 1May 18 – May 25
BarreApr 18 – Apr 25May 23 – Jun 6May 23 – May 30
WillistonApr 1 – Apr 8May 6 – May 20May 6 – May 13
MontpelierApr 7 – Apr 14May 12 – May 26May 12 – May 19
St JohnsburyApr 15 – Apr 22May 20 – Jun 3May 20 – May 27
BrattleboroApr 16 – Apr 23May 21 – Jun 4May 21 – May 28
WinooskiApr 1 – Apr 8May 6 – May 20May 6 – May 13
Saint AlbansApr 3 – Apr 10May 8 – May 22May 8 – May 15
Middlebury (village)Apr 7 – Apr 14May 12 – May 26May 12 – May 19
Saint JohnsburyApr 15 – Apr 22May 20 – Jun 3May 20 – May 27
MorristownApr 22 – Apr 29May 27 – Jun 10May 27 – Jun 3
LyndonApr 15 – Apr 22May 20 – Jun 3May 20 – May 27
RockinghamApr 11 – Apr 18May 16 – May 30May 16 – May 23
NewportApr 16 – Apr 23May 21 – Jun 4May 21 – May 28

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

Frequently Asked Questions

When should I plant cosmos in Vermont?

In a typical Vermont location, start seeds indoors Apr 11 – Apr 18, then sow outdoors May 16 – May 30, then transplant outdoors May 16 – May 23. Across the state, the outdoor planting window starts as early as May 6 in Burlington and as late as May 27 in Morristown.

When is the last frost in Vermont?

The average last spring frost in Vermont ranges from April 29 in Burlington to May 20 in Morristown, 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 Vermont

When to plant cosmos in other states

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