Canna lilies have tender bulbs. In warm climates, where winter temperatures rarely drop below 40 degrees F, mulching the flower bed would be sufficient to protect them frost and freezing. In most places, where fall and winter temperatures will drop below freezing, canna lilies will need special care to survive cold temperatures. You will need ample storage if you plan to over-winter your lilies.
Dig canna lily bulbs after the first frost. Start digging carefully 6 inches away from the base of the plant. Use the shovel to loosen the roots.
Place bulbs on a mesh screen that is resting on top of a garbage can. Label each individual bulb with a permanent marker. You can write directly on the bulb. Gently spray with water to clean off all soil.
Place mesh screens with bulbs on top, in a cool dry place. Allow to dry for three days, this will cure them and cause them to go into a dormant state.
Label paper lunch bags with the name of the bulbs you will be storing in it. Add the bulbs to the correct bags and cover with sand.
Store the paper bags full of canna lilies in a warm dry place such as a heated garage or basement. They can be kept in a closet in the house as well.