As we begin November, it is time for the dahlia grower to begin lifting and dividing their dahlia clumps. In a “normal” year, the November program at the Lane County Dahlia Society meeting would focus on this important task, with live demonstrations. Because of COVID restrictions however, we will not be able to hold our November meeting. Instead, we hope the following instructions will help you successfully complete this task.
1. The first step involves cutting down the dahlia stalk of each plant. Be sure that you have every plant correctly identified and labeled first. Then simply cut off the stalk 3-6” above the ground. This task is best done a few days before you wish to lift the clumps. This will allow the eyes on the tuber crown to swell, which in turn will make dividing the tubers much easier.
2. To lift the clumps, dig on all four sides of the clump, about a foot out from the stem. When the fours sides have loosened, carefully push the shovel under the clump and gently lift. Once the clump has been lifted, use a garden hose to remove most of the soil.
3. Sterilize your tools before you begin dividing. A solution of one part bleach to ten parts water is a very low-cost answer that kills the dahlia virus. Then cut off the remaining stalk. Look for the eyes near the crown and begin dividing. Each individual tuber must have an eye to grow the following year. After you cut off each individual tuber, remove any remailing soil.
4. After dividing and cleaning the individual tubers, many growers let the tuber soak in a bleach solution for 5-10 minutes. Then label each tuber with the variety name and let them fully dry.
5. After the individual tubers have dried, they are ready to be stored. There are several different storage methods, including wrapping the tubers in saran wrap or storing them in individual plastic boxes, filled with vermiculite or cedar shavings. No matter which method you choose, be sure once again that your tubers are clearly labeled.
6. The last step is to house your carefully stored tubers in a location that is no warmer that 50 degrees but also will not dip below freezing all winter. Then you can sit back and enjoy the restful days of Winter.
· For more in-depth instruction, we recommend visiting the American Dahlia Society web page at Digging, Dividing, and Storing Tubers – The American Dahlia Society