How are dahlia tubers best stored?
Rob Brandon, by email
Stefan says: You’ve seen two methods advocated. One involves removing the soil and storing them dry in crates lined with paper. The second is in pots of compost, which was said to avoid them drying out. I adopt a half-way house!
Practically all I know about dahlias I’ve inherited from my father, who was a regular prizewinner. The method that served him well for years was to brush off the soil but then store them in boxes full of dry, soil-less compost. We used compost that had been left over from growing bulbs in pots or for some other purpose.
If the compost is damp, they tend to rot and in those far-off days, the tubers were dusted with sulphur to help prevent that. This is no longer allowed so having the compost dry is even more important. It also acts as an insulator but it is still important to keep them somewhere frost-free.