[bigben]

I would risk some in the greenhouse. At worst the top stuff might die off like it does outdoors but if it has any sort of root it will pop up again in the spring. If you keep one or two on the windowsil you can hedge your bets.

[engineer]

Savbo, thanks just managed to find this

https://picasaweb.google.com/113276231157138920419/ForestGarden?gsessionid=n_Tz7ndGjgoJMYE9uizwLQ#5607084086965783938

AT first glance it would appear that the flower is not as blue as the ones i have seen

what do you think?

this is the comman one http://en.wikipedia.org/wiki/File:Symphytum_officinale_01.jpg


but also found this http://en.wikipedia.org/wiki/File:Russian_comfrey_close_800.jpg

[JohnB47]

the only way is to buy/get given some known Bocking 14 roots, as far as I can see

The wild stuff is great (that's what I use), it's just not quite as great at concentrating nutrients as B14 and it will seed like mad if you let it

Well, you could let one plant set seed and try growing plants from them. If it works, you don't have Bocking 14.

[RobertSongs]

I managed to get some going from seed in seed trays last autumn in my polytunnel (unheated) it came up a treat 4 of 6 germinated..but i felt it wouldn't have enough time to establish in the ground before the winter so i left it in the tray on my stageing and its still there each plant has lost a couple of leaves since then but it looks like it will be fine fingers crossed..its under a double layer of a plastic type fleece next to two potted lemon tree saplings and at the moment all seems well and we had two consecutive nights of heavy frost at the begining of the week..so i would agree with big ben but harden it off and give it some extra cover aswell..

[savbo]

Ta Engineer - you've enlightened me! It never registered in all my reading around the subject  that B14 was a hybrid...until now!

So yes, native comfrey is reddish with soft hairs and Russian Comfrey (inc B14) is blueish with stiff hairs. Native comfrey prefers wet places while Russian comfrey likes drier and waste ground...so most of the 'wild' comfrey I see around here is probably Russian...

(should have known all this, I supposed to be an ecologist!)

sav

[aelf]

Comfrey is a deep rooted perrenial so I would stick it in the ground outside when the ground warms up and forget about it til you need fertiliser! The leaves die back in the winter but, as others have said, it is almost impossible to kill it off and the leaves will regrow in the spring. I dug some roots up in the past (it grows wild on my plot) and piled them in a heap in full summer sunshine and 2 years later they were still going strong.

I harvest mine by driving a spade across the plant at ground level, completely decapitating the whole plant. Within a few weeks, it is fully regrown and ready to harvest again. This works for the wild variety (don't know about the hybrid).

Word of warning tho - the self seeding wild variety will take over your plot if you take your eye off it so, if you can, stick to the hybrid.

[engineer]

Cheers Sav, that is what this and other sites are all about, passing knowledge on or receiving some in return, glad to be of help

Cheers

[moonglow]

Well think i had a blond moment in the past couple of days, problem is im  a red head and male, anyway that aside remembered i did have a mini greenhouse outside full with my plantpots so moved that into the unheated greenhouse, and repotted the comfrey.

2 kept inside.
5 brought inside every night.
4 kept in mini greehouse, which is also in unheated greenhouse.

Last but by no means least, found out when repotting the comfrey that i have placed one of the cuttings in upside down, but it still shooted.