FrostCal

When to Plant Dahlias in Delaware

In a typical Delaware location, plant outdoors Apr 14 – Apr 28. Across the state, the outdoor planting window starts as early as Apr 6 in Claymont and as late as Apr 26 in Hockessin.

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
WilmingtonApr 14 – Apr 28
DoverApr 11 – Apr 25
NewarkApr 14 – Apr 28
MiddletownApr 14 – Apr 28
BearApr 14 – Apr 28
BrooksideApr 14 – Apr 28
GlasgowApr 14 – Apr 28
HockessinApr 26 – May 10
SmyrnaApr 11 – Apr 25
Pike Creek ValleyApr 14 – Apr 28
MilfordApr 18 – May 2
ClaymontApr 6 – Apr 20
North StarApr 14 – Apr 28
Pike CreekApr 14 – Apr 28
Wilmington ManorApr 14 – Apr 28
SeafordApr 18 – May 2
GeorgetownApr 11 – Apr 25
ElsmereApr 14 – Apr 28
EdgemoorApr 14 – Apr 28
New CastleApr 14 – Apr 28

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

Frequently Asked Questions

When should I plant dahlias in Delaware?

In a typical Delaware location, plant outdoors Apr 14 – Apr 28. Across the state, the outdoor planting window starts as early as Apr 6 in Claymont and as late as Apr 26 in Hockessin.

When is the last frost in Delaware?

The average last spring frost in Delaware ranges from March 30 in Claymont to April 19 in Hockessin, 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 Delaware

When to plant dahlias in other states

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