When to Plant Sunflowers in New Hampshire

In a typical New Hampshire location, sow outdoors May 10 – May 24. Across the state, the outdoor planting window starts as early as Apr 28 in Salem and as late as May 21 in Berlin.

Method Direct sow
Days to maturity 70–100 days

Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.

Sunflowers Planting Dates by City

CityDirect sow
ManchesterMay 7 – May 21
NashuaMay 7 – May 21
ConcordMay 15 – May 29
East ConcordMay 15 – May 29
Derry VillageMay 7 – May 21
DoverMay 10 – May 24
RochesterMay 7 – May 21
SalemApr 28 – May 12
MerrimackMay 7 – May 21
KeeneMay 21 – Jun 4
DerryMay 7 – May 21
PortsmouthMay 11 – May 25
BedfordApr 28 – May 12
LaconiaMay 7 – May 21
LebanonMay 16 – May 30
WindhamMay 10 – May 24
ClaremontMay 21 – Jun 4
PelhamMay 10 – May 24
SomersworthMay 7 – May 21
LondonderryApr 28 – May 12
DurhamMay 15 – May 29
HamptonMay 11 – May 25
BerlinMay 21 – Jun 4
ExeterMay 11 – May 25

Showing the 24 most populous of 24 New Hampshire cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all New Hampshire cities.

Frequently Asked Questions

When should I plant sunflowers in New Hampshire?

In a typical New Hampshire location, sow outdoors May 10 – May 24. Across the state, the outdoor planting window starts as early as Apr 28 in Salem and as late as May 21 in Berlin.

When is the last frost in New Hampshire?

The average last spring frost in New Hampshire ranges from April 21 in Salem to May 14 in Berlin, based on NOAA 1991–2020 climate normals.

How long do sunflowers take to grow?

Sunflowers typically take 70–100 days from planting to harvest. Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.

Other Crops in New Hampshire

When to plant sunflowers in other states

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