FrostCal

When to Plant Dahlias in Maine

In a typical Maine location, plant outdoors May 9 – May 23. Across the state, the outdoor planting window starts as early as May 2 in Lewiston and as late as May 23 in Sanford.

Method Plant out (slips, crowns, or tubers)
Days to maturity 90–120 days

Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive.

Dahlias Planting Dates by City

CityPlant outdoors
PortlandMay 3 – May 17
LewistonMay 2 – May 16
BangorMay 11 – May 25
West ScarboroughMay 3 – May 17
South PortlandMay 3 – May 17
South Portland GardensMay 3 – May 17
AuburnMay 2 – May 16
BiddefordMay 16 – May 30
SanfordMay 23 – Jun 6
SacoMay 16 – May 30
AugustaMay 4 – May 18
WestbrookMay 3 – May 17
WatervilleMay 9 – May 23
BrunswickMay 9 – May 23
York BeachMay 8 – May 22
Wells Beach StationMay 16 – May 30
OronoMay 8 – May 22
LisbonMay 22 – Jun 5
North BathMay 17 – May 31
BrewerMay 11 – May 25
Presque IsleMay 21 – Jun 4

Showing the 21 most populous of 21 Maine cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Maine cities.

Frequently Asked Questions

When should I plant dahlias in Maine?

In a typical Maine location, plant outdoors May 9 – May 23. Across the state, the outdoor planting window starts as early as May 2 in Lewiston and as late as May 23 in Sanford.

When is the last frost in Maine?

The average last spring frost in Maine ranges from April 25 in Lewiston to May 16 in Sanford, based on NOAA 1991–2020 climate normals.

How long do dahlias take to grow?

Dahlias typically take 90–120 days from planting to harvest. Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive.

Other Crops in Maine

When to plant dahlias in other states

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