Posted: 19/08/2013 at 13:32
I have dahlia that are from tubers and seed. I will be waiting to take seed from mine then lifting them all after first frost. Chopping down and storing in shredded paper upside down. Then in spring pop into compost and off you go again!! I take cuttings when they start again. I will mark my plants/tubers with a label of the colour so when I take cuttings I know what I have got. As this year I didn't label and I managed to get all my new cuttings in yellow!!! Oops!!!!
I save my seed as an insurance policy but with seed you won't get true plants you get weird and wonderful colours but that is half the fun.
stake and support the plant, it will help it, ball ways deadhead regularly then just easy off late summer to save a few heads for seed. I managed to propagate and prick up 357 dahlia plants this year and gave to my farther for his large borders, they look awesome! He won't lift his he lets them take their chance but I lift mine as I want to keep my original specimens (if that is the right term!)