dividing massive dahlia roots

Question

I was out walking and i found two enormous clumps of dahlia’s that had been thrown away. This was in September of last year, being a gardener I was horrified so took them home and put them into extra large flower pots, watered them and low and behold they started to make new growth it was a little late in the season and they never made flowers so after a bad frost I brought them indoors and let them dry out now I want to split them but don’t know where to begin as the are such a mass. I know you should discard the mother tuber and any rotten ones but if I just start pulling them apart I may cause even more damage is there an easy way . Should I let them start to make growth then separate or should I do some pulling now to get rid of the old dirt and make it easier for later. I am hoping to bring something back to life. These root balls really are a mess and a mass.
Irene

Answer 1

It’s best to wait until you see some “eyes” growing so you can determine how to divide the clump, as described in this article:
https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/dividing-dahlia-tubers.htm
Each piece should have one or two eyes after you separate them. Any that are rotten or that don’t have eyes should be discarded. It might be hard to determine which is the mother tuber, so don’t worry about discarding that.