Storing Dahlia Tubers
After frost blackens the dahlia tops, wait for a dry day – hah! HOPE for a dry day – within the next week or so, before you dig up the tubers. Turn the clumps upside down to dry in the sun, then remove any damaged tubers and lightly brush off loose dirt. Pack in plastic-lined cardboard boxes, surrounded by packing peanuts. If you give each variety its own container, any old marking label will do, assuming you use indelible ink.