Year-Round Gardening: Take steps to enjoy dahlias for many seasons | Lifestyle
Dahlias are one of my favorite flowering plants, with a long flowering period from early summer to the first frost. Deer and rabbits don’t seem interested in eating these showy plants. While they’re usually grown as an annual flower, it’s easy to store the roots over the winter and enjoy the same plants for many years to come.
Here are the steps to hibernate:
Wait until a few days after we have a frost that causes the foliage and flowers to recede. You have to dig them up before the ground freezes.
Make sure you’ve separated and labeled the roots by variety.
Use clean, sharp secateurs to trim the stems back to a few inches above the ground. It is a good idea to sanitize the secateurs between plants with a 10% chlorine bleach solution. This will prevent fungus from spreading.
With a spade fork, dig about 12 inches from the plant and gently lift it up.
Once the soil has broken up, lift out the entire plant. Carefully remove soil from around the roots. Dahlias are tubers; their root system contains swollen underground storage organs, similar to potatoes. Like potatoes, the dahlia tubers form eyes, new growth points for the plants of the next year. With dahlias, these eyes are at the top of the tubers next to the stem of this year’s plant. If you break off one eye, it won’t be able to drive out in the spring. Once most of the soil has been brushed off, you can wash off the remaining soil with a garden hose.
Place the tubers on a flat, clean surface; Cardboard works fine. Let them dry completely. It will take several days.
You can apply a fungicide to the tubers before storage. If your plants have had fungal problems like powdery mildew, this is likely a good precaution.
Place your tubers in a cardboard box and lay them flat. If you are making multiple layers, place some brown paper between the layers. To control moisture, you can place them in peat moss or wood shavings. The goal is to keep the tubers moist enough to prevent them from drying out, but dry enough to prevent rot.
Store them in a dark place where the temperature stays between 40 and 50 degrees. An unheated garage can work well if you remember to bring the box in when it’s freezing. Keep a refrigerator thermometer nearby to monitor the temperature. Check the moisture level every couple of weeks and spray it with water if it is too dry. Too dry is better than too wet.
In the spring, you can plant the roots when the danger of frost has passed.