By Thecat
Lancashire,
United Kingdom 
Hi all & a very happy new year.
Because of ill health I've only just got around to digging up my dahlia tubers. Now I have 2 questions.
First, am I too late and so wasting my time?
Secondly, assuming I'm not wasting my time, I have several clumps. Some have massive tubers and I would like to know if it's ok to reduce the clumps by removing the large tubers and just keeping the smaller (new?) tubers for replanting in April/March. Last spring I replanted the previous years saved tubers & I tried taking cuttings but was not impressed with my new plants which produced foliage but little blooms but the replanted tubers flowered well. So the tubers I'm referring to are 3 years old, could it be time to start again with new stock?
27 Jan, 2015
Answers
meant to say sorry you have been unwell, lets hope 2015 is better for all of us.
28 Jan, 2015
Thanks Seaburn for your comments and good wishes.
28 Jan, 2015
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If the tubers are firm then no you haven't wasted your time. if they have a few mushy tubers remove them. stand them upside down and store them in either dry compost or sawdust.
If you haven't lifted them I would leave them and cover with a thick mulch of straw or compost.
The tubers themselves don't grow a new plant unless they have an eye on them from the growing point.
The tubers provide food for the new growth so the more tubers the bigger and 'better' the plant should be.
Cuttings may well not flower that well in the first year but they should have produced a tuber which will mean it will be bigger this coming season. I have some dahlias that are over 10yrs old now.
so no you don't need to replace them.
28 Jan, 2015