It varies so much from plant to plant TripleB. I had one plant broken off early(on another thread posted recently) and there was only one decent tuber formed, a couple scraggly ones that were more like fat roots, and the mother tuber which will be tossed. Others will have a dozen keepable tubers, but for me that is an exceptional number. Average: maybe 5-6?

Dig em up and see for yourself LOL!

Poochella - is the mother tuber not viable anymore? Is it quite visibly bigger, or shrivelled? Does one always have to throw it away at the end of the season? Thanks!

Anna

Anna, sometimes the mother tuber will go on to grow, but the idea seems to be that it is nearly 'used up' and won't go on to produce a very robust plant, if at all. I planted one this year of Wildwood Marie and the plant was indeed very slow, much smaller than a fresh tuber-produced W.Marie plant and the flowers are smaller too.

You can see if the mother tuber will produce shoots next year for cuttings, which is why I kept a couple of them.

They are generally darker looking than a new tuber taken out of the ground. You can see the difference in color here. Mother on the left and new tuber/s to the right.
{{gwi:661799}}

And here as well. This is my Show and Tell which got crushed/broken by a falling neighbor plant or two.
{{gwi:661802}}

But if you get the amazing beet colored tubers the 'different color' theory goes right out the window! I can't recall if the mother was obvious on the pink clump, probably. Maybe it had a cane and shawl.
{{gwi:660183}}

Sometimes the mother has rotted right away to nothing & sometimes she's there in all her glory. We keep the mother in case the babies rot or shrivel up. She's stored seperately in case SHE rots-- what a lot of rot is associated with dahlias! Also mothers will put out good shoots for cuttings- & usually earlier than the newer tubers will.

Poochella, they're coming for me! save me!
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!!!!