Posted: 25/01/2015 at 14:50
I lift my Dahlia in November and regrow in Feb/March, so the dormancy period is as short as possible. I left them, allow the soil to dry off, cut off what needs to go and then repot with soil. That keeps the tubers turgid. I would not store them bone dry. So I advise you to repot with dryish compost. but keep them dark.