By Barbarak
North Yorkshire,
United Kingdom 
i have started to unpack my dahlia tubers again after checking them a couple of months ago. some individual tubers have gone soft and many have white ? mould on them. Is it OK to plant out the ones with mould on them; they feel firm and should I cut out the soft ones as others are still firm?
8 Mar, 2018
Answers
the white could be fungal but not a problem. if firm pot them up keeping them barely damp in a frost free place. the soft ones could just be lacking in moisture, so pot them up and see if the grow. I usually only discard if they are mushy or smell really bad.
8 Mar, 2018
I would be inclined to remove any rotten tubers and discard them. The ones with white mould, you could wash off and sprinkle with Flowers of Sulphur. (Only if you can find some as I believe it has been banned my EC). If you have a green house or window bench in a garage; pot them up individually and grow them on until the spring frosts have passed.
8 Mar, 2018