how long before a new strain develops from your efforts
These are the developed flowers!
If you mean how do
I develop them next year its simply a case of I will save the tuber/s and store them over winter as you would do with any dahlia.
Next year I will give them a lot more attention to try and refine them, i.e. get the inner ring of petals more regular in shape and less wayward i.e flatter to the large petals.
I will also disbud to encourage larger flowers.
This year I just let them grow at will to see what comes of them and I will only save the ones with potential meaning this year I will dump the other fifty odd.
Where did you get the original seed from
They are just an ordinary packet named 'Dandy' I picked up from Kings for around sixty pence.