Photo: from open sources
Digging up dahlias for the winter – why and how to do it
Dahlias are a heat-loving crop, where the soil naturally grows does not freeze. Therefore, the agricultural technology for growing dahlias in our climate requires their obligatory digging before the onset of winter cold.
Dahlia tubers are fragile, do not tolerate dampness well, and are susceptible to various diseases and damage by pests. Some gardeners leave the underground part of the plant in open ground for the winter. To prevent the plant from freezing, they insulate the soil above the place where the dahlia grows. However, the tubers will not withstand temperatures even close to zero. Constant exposure to moisture during the dormant period is also dangerous for the dahlia root system. Therefore, even if the plant is well covered, but left for the winter, it will die.
When to dig up dahlias for the winter
You should focus on weather conditions and the condition of the plant. It is best to dig it up after the first frost, so that the underground part has time to ripen and prepare for a state of dormancy, and the above-ground part of the dahlia and flower should be caught by frost.
That is, dahlia tubers should be dug up after the first autumn frosts, when the plant stems wither and acquire a distinct brown color. When the air temperature first drops below 0 °C, you need to wait a couple of days so that the future planting material undergoes a slight cold hardening, and then dig up the plant on a dry, fine day.
How to dig up dahlias
- Trim, preferably with pruning shears, the dead above-ground part, leaving a “tail” of 10-15 cm. This will make it more convenient to pull the bush out of the ground.
- Gently dig up the plants with a shovel if they are growing in dense soil or with a pitchfork if the soil is loose. Be careful not to damage the tubers and root collar.
- Cut the stems to a height of 2-3 cm, leave the dug bush in this form for a while so that the bush dries out.
- Carefully remove excess soil from the tubers.
- Transfer the tubers to a warm, dry, well-ventilated place where they can dry completely. This may take about two weeks.
- Inspect dried dahlias for diseases and pests; infected specimens must be destroyed. Rotten and broken parts of the root are cleaned and disinfected.
How to store dahlias in winter
- The best temperature for wintering dahlia tubers is +3.+10 C. If the temperature is close to zero degrees, there is a risk of tubers being damaged by the cold. Temperatures above +10°C activate vegetation, which leads to weakening of the rhizome.
- Optimal air humidity is 60-70%. In winter, dahlias are periodically lightly moistened.
- Tubers will be better stored in the dark, in which case they are at rest.
- Dahlia tubers can be stored on a balcony or loggia, in a basement, cellar, and even at home. To do this, lay them out in layers in boxes or containers, sprinkling each layer with dry sand, sawdust, peat, vermiculite or any other bulk hygroscopic material. The roots should not touch each other and should be completely covered.
