Dahlias are not frost hardy. So that you can enjoy the blooms again next year, you have to overwinter them indoors.

Dahlia Overwintering Instructions
➥ Step 1: Cut back dahlias
Cut off the flower stalks of your dahlias at ground level once the flowers have withered.
➥ Step 2: dig up dahlias
Use a digging fork to carefully lift the dahlia tubers out of the ground and remove them as far as possible. Rinsing under water is also possible. Then let the tubers dry in a warm place for a few days.
➥ Step 3: Store Dahlias
Now take a wooden box lined with newspaper and fill it with a thin, dry layer of peat and sand. Then place the tubers on top and then completely cover them with the peat-sand mixture. Important: the tubers must not touch each other!

You only have to place the box in a dark and cool place (maximum 5 degrees room temperature) and the topic "Overwintering dahlias" is already complete.
➥ Step 4: Plant dahlias again
You can then plant the tubers out again from May. Either directly in the garden or in pots. In any case, wait for the ice saints!
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