Winter Storage of Tender Bulbs

Michele K. Koskinen

There are bulbs you leave in the ground to multiply and there are bulbs that must be stored for the winter. Those fanciful bulbs that grow in our spring and summer gardens like caladiums, elephant ears, gladiolus, canna and others are considered "tender bulbs". They are mostly tropical or warm growing plants that will not survive the cold northern winters.

Although they are not technically a "bulb" they are called that for convenience in many growing markets and this blog. Tender plants usually are from corms, tubers, roots, and rhizomes and must be stored for the winter as they are not winter hardy. Many, like a recent elephant ear purchase, are expensive so it is worth the effort to store them for the winter. Some will grow as houseplants if you have the right light and humidity in your home, it is worth considering.

Using my garden as a giant experiment from year to year, I am going to attempt to lift and save the tender bulbs in my containers. Canna, begonia and caladium are favorites on my deck. This year I also purchased a beautiful elephant ear. So time to research the how. The why is curiosity and getting started a little early and for those that have many tender bulbs, the cost of repurchasing every year also can become a reason to lift and store these bulbs.

Tender Bulbs should ideally be dug after the foliage has dried or a light frost has killed the foliage. 

The bulbs should not be allowed to freeze. They should then be "cured" before storing in the medium of choice. This year the foliage is just beginning to dry in my garden and a light frost is expected. I will be removing the bulbs and hope for the best in the curing process. Late November is upon us     

A few thing to remember:

          1. Storing these "bulbs" require two major requirements with other guidelines for specific plants. Cold and Dry is the name of the game and additionally lifting them right before or after the first frost is best for survival.

          2. Locate the bulb, and then using a fork inserted a few inches away gently pry the plant from the ground. Shake off the excess soil and allow the foliage and bulb to completey dry "cure" in a sheltered warm space.When digging up the bulb from the garden, dig gently so as not to damage the plant. Cuts on the bulbs before storage can bring in disease. 

          3. Make sure your bulbs are free of disease and fungus. Some resources recommend sprinkling an insecticide-fungicide on the bulbs.

          

To make your efforts more successful be mindful of temperature and storage materials. I only grow caladiums, canna and begonia so my information will only cover those plants. Follow the direction for storage for each individual plant cultivar, and use the links below to gain additional information for your project.












I have compiled and combined storing instructions for my specific plants.

• Tuberous Begonia: Allow a frost to kill the tops, but do not allow the tubers to freeze. Lift and let tubers dry for one week, with about 5 inches of the foliage still in tact. Remove excess soil and foliage and store in peat moss or sawdust at 50 degrees F. Repot in early spring and keep warm, 68 - 75 degrees F. Move to a sunny spot when shoots appear. Keep evenly moist, but not wet. Plant outside after all danger of frost.
• Caladium: Lift caladium plants before frost and allow them to dry in a warm spot. Cut back the foliage after it dies. Caldium bulbs don't like to be stored in cold temperatures. Keep at 50-60 degrees F. Pack loosely in peat moss. Repot up in early Spring, about 2 inches deep, knobby side up. Keep the soil moist and warm - 75 - 80 degres F. Move outdoors after all danger of frost.
• Canna: Allow frost to kill the tops, but do not allow the rhizomes to freeze. Carefully lift the plants and cut off the dead tops . Hose off excess soil and allow to dry. Rhizomes can be wrapped in newspaper and stored in paper bags or cardboard boxes, at 45 to 50 degrees F. Very easy to overwinter. Cannas can be divided by hand. Break apart, insuring there are at least 3 eyes per division. Repot in early spring or plant directly in the garden once the temperatures remain above 70 

Videos that are helpful

video..marthastewart.com how-store-bulbs-winter

www.youtube.com

Links:
pennlive on storing bulbs
extension.psu.edu
extension.minnesota