FrostCal

When to Plant Dahlias in Oregon

In a typical Oregon location, plant outdoors Apr 10 – Apr 24. Across the state, the outdoor planting window starts as early as Feb 18 in Beaverton and as late as Jun 16 in Altamont.

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
PortlandMar 4 – Mar 18
EugeneApr 18 – May 2
SalemApr 10 – Apr 24
GreshamMar 23 – Apr 6
HillsboroApr 23 – May 7
BeavertonFeb 18 – Mar 4
BendJun 13 – Jun 27
MedfordApr 15 – Apr 29
SpringfieldApr 18 – May 2
CorvallisApr 24 – May 8
AlbanyApr 24 – May 8
TigardApr 8 – Apr 22
AlohaFeb 18 – Mar 4
Lake OswegoMar 25 – Apr 8
KeizerApr 10 – Apr 24
Grants PassApr 15 – Apr 29
Oregon CityMar 25 – Apr 8
McMinnvilleApr 12 – Apr 26
RedmondJun 16 – Jun 30
TualatinApr 8 – Apr 22
West LinnMar 25 – Apr 8
WoodburnMar 23 – Apr 6
Forest GroveApr 23 – May 7
NewbergMar 28 – Apr 11
WilsonvilleMar 25 – Apr 8
RoseburgMar 30 – Apr 13
Klamath FallsJun 16 – Jun 30
AshlandMay 13 – May 27
MilwaukieMar 4 – Mar 18
BethanyApr 23 – May 7

Showing the 30 most populous of 68 Oregon cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Oregon cities.

Frequently Asked Questions

When should I plant dahlias in Oregon?

In a typical Oregon location, plant outdoors Apr 10 – Apr 24. Across the state, the outdoor planting window starts as early as Feb 18 in Beaverton and as late as Jun 16 in Altamont.

When is the last frost in Oregon?

The average last spring frost in Oregon ranges from February 11 in Beaverton to June 9 in Altamont, 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 Oregon

When to plant dahlias in other states

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