Begonias: Wait for the first frost before digging tuberous begonias. Cut the stems back to an inch or so and allow the tubers to dry in a box or basket until most of the soil brushes off. I put the tubers inside paper grocery bags and hang them in our pump room, an area that stays below 50 degrees all winter long.
Dahlias: Dahlia roots need to be dug after the foliage has been killed by frost and stored at temperatures just above freezing. Cut the stems off at the soil line and carefully dig the tubers. Leave them outside for half a day with the stems turned downward to drain. Allow the tops to freeze before you dig the dahlia tubers in the fall. Once they dry off well, store the tubers on a sheet of plastic covered with spaghnum moss in flats in a cool basement. To keep them from shriveling over the winter, sprinkle the tubers lightly with water in February.
Gladiolus: Gladioluses also need to be dug in the fall and stored during the winter. After digging, cut the foliage back to half an inch from the tip of the corm and lay the corms one layer thick in a warm spot out of the sun. When the corms are completely dry, I break off the parent corm and discard it, saving only the new corms. I slip them into a paper bag that I hang in a basement room where the temperature ranges from 40 to 50 degrees for the winter months.
Some plants require time in the ground over the winter in order to germinate. Pot up seeds and bulbs that require this “cold stratification” and leave them buried by snow through winter. You can also place any potted small trees and perennials in a protected spot and cover them with wood chips to help them avoid freeze-and-thaw cycles.
Learn how to prepare you garden for the coming cold in Putting the Garden to Bed for Winter.
Margaret Haapoja is a freelance writer living on Little Sand Lake near Grand Rapids, Minnesota. She is the recipient of a “Life Award” from the Minnesota State Horticultural Society, and an award-winning garden writer.