Dahlia’s are tuberous plants known for stunning late summer blooms. Yearly maintenance of the dormant dahlia tubers rejuvenates and preserves the tubers.
At the end of dahlia season cut off the stocks of the plants and allow the plant to heal for about a week before being removed from the ground. During the digging process be careful of cutting the tubers or tearing them off of the stock which is essential for the division process. The best environment for dahlias to spend the winter is in a cold humid environment. The tuber shown below spent the winter in redwood fir bark under trees and was lifted in late February for dividing.
The essential materials are a sharp knife, cutting board and sulfur. The trick to dahlia division is finding the eye of the plant which normally is where the tuber meets the stock. When the eye is located use the knife to cut the stock with the eye and the connecting tuber. The eye must remain connected to the tuber in order to produce a viable plant. If the eye is not apparent you can use a blind tuber by cutting the tuber off the stock allowing for potential eye growth. Then dip the wounds of the tubers into sulfur to prevent growth of fungus and place on top of a pot of soil. Each stock will differ in the amount of tubers that are viable and can range from 1 to 20 new plants. Keep the tubers in a warm moist environment and add soil as the dahlia grows. Once you have a healthy viable plant it is time to go into the garden.
Carmody and Sun 