Posted: 18/08/2014 at 21:52
to take cuttings
I have a pamphlet somewhere written by Lawrence Hills, who developed Bocking 14.
It had a breakdown of which comfrey clones were best for fertiliser.
I have collected comfrey from the flood plain at the side of the Trent. If there is nowhere near you that you can collect it, I would always recommend the sterile clone Bocking 14. If you grow a clone that flowers, make sure you cut off flowers before they form seed, otherwise it spreads all over the garden.