When should I split the tubers, in the fall when I dig them up ,or in the spring before I plant them?
Splitting Dahlia Bulbs
Certified GKH Gardening Expert
It would be better to do this in spring. This is when you will be able to tell what will make a good split. This article will give you more information: https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/dividing-dahlia-tubers.htm