Granny23 I have grown comfrey in the past and used it to make my own ointment. It contains Allantoin which is a great tissue regenerator. Another name is bone-knit, but there is speculation that it is carcenogenic if taken internally.
It looks a bit like borage.
Actually I might grow it again now you've reminded me.
I still have leeks, winter brassicas, oka, in some beds but have cleared out others (I have a big allotment). The soil here is very clayey (is that a word?) and our allotment was in a poor state when we took it over two years ago. I need to get lots of fibre into it. Like Jenny I dig in my runner bean roots, stalks, etc. in fact anything I can find.
Any more advice, thoughts would be welcome.