In the spring tender corms, tubers are planted in pots, baskets or the ground to add colour and variety to the landscape. They are relatively easy to grow and usually make a big impact on the yard. In the fall tender roots can be treated as annuals and discarded or dug up when the weather turns cold and stored over winter to be planted next spring.
Dig the roots once the tops are lost to frost or starting to dry out. With Dahlias, cut the tops off leaving the 4 – 6 inches of the stem. Carefully dig the roots out with a fork and allow them to dry for a few hours in the sun before moving them indoors to dry further. If possible spread them out on a dry surface and allow them to dry completely.
When the soil brushes off easily, remove all traces of soil and examine for signs of injury or disease. At this point, discard any item that is not in top condition. Storing injured or diseased roots is not wise as diseases and mould spread quickly from one stored item to another.
Dahlia roots can be left as is or separated into individual tubers. When cutting the tubers apart, allow the cuts to callus before they are stored. Removing excess materials reduces storage space but diseases and fungus can enter any cut area that has not been completely callused over.
To prevent Dahlia tubers from becoming dehydrated, they are packed in materials such as sphagnum moss or vermiculite and stored in a cool damp area.
Allow gladiola roots and stems to dry after they are dug up. The roots and tops will break away from the corm when they are completely dried and ready to be stored. Place the corms in a mesh bag and store in a cool dry area with good air circulation.
Dig up tuberous begonias after the first frost. Remove the dirt and allow the rest of the dirt to dry and stems to wither and fall off. Inspect for cuts and diseases. Place tubers in individual paper bags then place in a cardboard box. Store the box in a cool but not cold area.
It is possible to store Dahlia and begonia roots by leaving the tubers in the container and allowing the soil to become dry completely. Store the potted roots in a cool area that will not freeze.
Those that are worried about diseases can use a fungicide; to protect the roots. Always be sure to follow the instructions on the fungicide container.
Check on the roots periodically throughout the winter removing any item that is compromised by mould or disease. Mist tubers if they are starting to become soft and shriveled.
Horticulturist Linda Tomlinson has gardened in Central Alberta for over 30 years. She can be reached at email@example.com.