Ornamental plants like petunias, begonias, dahlias and fuchsias won’t survive even a mild Southeast Alaska winter outside. We need to bring sub-tropical plants into a space that won’t freeze, says Master Gardener Ed Buyarski.
“If they hit 32 degrees, they’re probably toast,” Buyarski says. “I guess frozen, not toast.”
Once a hard frost knocks back the foliage of dahlias and begonias, Buyarski recommends removing the tubers. Wash off the dahlia tubers while allowing the begonia tubers to dry out before putting them in a labeled paper bag and storing it in a place that does not freeze.
Dahlia tubers can also be stored in dry sawdust, dry shredded paper or dry straw in a paper grocery bag. They can be divided now or in the spring.
Fuschias should be trimmed back to 4-to-8 inch stems and can overwinter in a place colder than 40 degrees, like a root cellar. But Buyarski says check on them regularly to make sure they don’t dry out over the winter.