Part of our long-term plan was to get some comfrey started in at least one of the worn-out fields we own to start pulling up nutrients and allow for some chop-and-drop soil improvement over time. With a million projects going on this (first) spring we just never got to the comfrey project.
NOW we find some comfrey growing up at the beginning of the entrance road to the property. Not much, maybe 10-12 plants. Prior owner may have started them. The plants are about 2-3 feet tall and have started to flower. We are zone 5 and after a long, wet, cool spring I'm surprised to see them moving up and along so quickly... I'm thinking it might be time to use these plants to launch the planned comfrey-field sooner rather than later.
The question is - is this a good time to dig them up or otherwise propagate them? if so - how to do it? if not - when?
I've heard that the roots of Comfrey can be cut into pieces and this seems the best way to quickly multiply numbers. Should I did the plants and cut up the roots? If I plant these now can I still expect adult plants by the end of summer? will they flower and seed?
... or should I wait through the season for seeds and gather and disperse seeds and root cuttings then ?
Over here, it's recommended to plant lengths of root in Autumn. 'length' is a relative term: it'll grow from really small bits! But seriously, the suff is pretty hard to kill. I'd just stick it in when I had the opportunity. The plants will take a couple of years to get going, and really hit their stride in three. I wouldn't harvest them till at least the second year. The thought of comfrey with viable seed scares me a bit! In NZ it all seems to be the sterile 'Bocking 14', so it's very controllable, unless a twit with a tiller gets to it...
i divide my comfrey all through the growing season, i have less susccesful results in the fall.
dig up as much of the thick root as you can, it should be about as thick as your finger. dig it up and cut them into 2 inch sections. lay flat in a tray full of sand and compost. cover lightly and dont let it dry out. once rooted either place where you want them. or in a pot for a week or so until more roots establish. do not leave in a pot long term, comfrey HATES pots.
The ultimate goal of farming is not the growing of crops, but the cultivation and perfection of human beings. - Masanobu Fukuoka
I made a big nonsense: I planted 100 (!) comfrey root cuttings (they were so cheap) under fruittrees. So far so good, but I interplanted the fruit trees with gooseberries and currants too. Needless to say that they severely sat these poor shrubs back. since then I try to dig out the comfrey and transplant it to more suitable places. But maybe I should transplant the berry plants. In short: you can throw the comfrey root on the top of your roof and it will still grow. I harvested heaps of the leaves in the first year and several times. But find a permanent position as it is difficult to get rid of. It is not invasive in the sense that it spreads endlessly, but if you dig it out you will likely leave a bit of root in the soil which will regrow.
I am looking at a property that has a lot of dirt roads on it. I was thinking to plant comfrey in the middle of the roads - between the tire tracks. That would certainly help control its spread. I'd just need to mow it down more frequently (and make certain to control any oil leaks on my vehicle(s).