How to Overwinter Dahlias

How to Overwinter Dahlias

Tender dahlias are dazzling summer flowers, and their growth as annuals or perennials depends on your hardiness zone.

Botanically, dahlias are cold-tender herbaceous perennials grown from tubers, with a preference for warm days and moderate to coolish nights.

Late season darlings, they put on a magnificent and lengthy floral show, blooming from mid-July until they’re felled by frost.

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These showy ornamentals come in a wide range of colors and sizes, with 15 different flower types and almost 60,000 cultivars – so there’s no shortage of choice for your garden!

Natives of Mexico and Central America, dahlias are hardy in USDA Zones 8 to 11, where they can be grown as perennials.

In Zones 7 and below, they’re typically grown more like spring-planted annuals that are then lifted in fall and stored for winter.

But with the right protection, many gardeners overwinter them in Zones 7 and even 6 with a successful return each spring, no digging required. I’ll tell you how in a bit.

So, whether you grow them as annuals or perennials, we’ve got you covered when it comes to overwintering tender dahlias.

Here’s everything you’ll find up ahead:

Overwintering is the practice of providing tender plants with protection to survive cold winter weather.

It’s most beneficial for tropical and semi-tropical plants that are cold tender and can’t survive freezing temperatures.

But also helps to protect against freeze and thaw cycles that can displace roots and heave crowns, exposing them to the elements.

To overwinter tender tubers, they must be located in well-draining soil because