Temperate climate "comfrey circle"

Did I just invent this? Do you think it would work?

comfrey circle design

The idea is that I could throw any weeds into the depression in the centre, the comfrey would
a) act as a barrier to prevent them spreading out of the hole and
b) use the nutrients to grow and make mulch material or greens for liquid plant food.

I have grown banana (!) but they did eventually succomb to the frost (and weren't fruiting plants)

What other plants might be suitable for this sort of arrangement?

Just today I propagated comfrey around a raised bed for much the same reasons.
My raised beds are filled with half composted materials, and the comfrey is there to capture and cycle nutrients.

I put beds like this next to every tree I'm trying to feed.
Its a way to create a reservoir of nutrients and moisture.

A circle of elderberry live stakes could be interwoven with vines and the resulting enclosure filled with compostable material.
This is a version of a willow poop beast, one that skips the poop and grows edible plants

Figs are supposed to do well in these circumstances, according to this thread:
https://permies.com/t/46085/composting/Growing-compost-pile

Of course, squash is notorious for loving unfinished compost, but that same thread mentions tomatoes.
I've seen grass fed corn do quite well, so that's another possibility.

Interesting idea. I reckon you'd want Bocking 14 specifically so it doesn't seed into the middle and compete with whatever you're composting. The only thing I'd wonder about is how quickly the roots colonise inward, comfrey is pretty aggressive underground too.

I don't know that the colonizing-inward would really be a problem. Just keep tossing dead weeds in the middle. If the comfrey can grow through it, then you have more dynamic accumulation taking place and next year maybe you'll toss down even more weeds.

I've been noticing that comfrey planted in a clump and left to grow, invariably topples over outward. I wonder if you could just plant one of those, wait for the topple and then pile the center up with your dead weeds and mulch and whatever, causing the comfrey to colonize outward and allow the cavity at the center. Though that wouldn't have the earthworks element on display in Nancy's diagram.

Christopher Weeks wrote:I wonder if you could just plant one of those, wait for the topple and then pile the center up with your dead weeds and mulch and whatever, causing the comfrey to colonize outward and allow the cavity at the center. Though that wouldn't have the earthworks element on display in Nancy's diagram.

You could get a ring if you had a well established plant and tried to dig it out (ask me how I know!) That would also give you a central depression!

I'm not sure which comfrey variant I have but I'm certain it is one of the sterile ones - it does tend to regrow from bits of root left behind though.

Where I live, the comfrey, any variety, really looks terrible and dies way back if you don't chop and drop it every month or two from Apr to Nov. During the regrow period, you'd have an opportunity for latent seed growth in the middle. However, if you chop and drop to the middle, it'll smother whatever latent seeds that may be there.

If I don't chop my comfrey it grows huge, flowers and flops over....and then grows again from the centre! I was hoping to get some harvest of mulch from the comfrey, but you're right - cutting back will reduce the barrier effect, although I'm less worried about seed germination than buttercups and silverweed carrying on growing. It will take a year or so for the comfrey to get established, but I'm thinking I may try this in the centre of my new kitchen garden and see how it works

I couldn't resist buying a baby comfrey plant last spring from a garden centre. When home I wondered where to plant it. I ended up planting it at the foot of a composting pile I have in my garden on open soil. So now as the decomposing pile of mixed garden waste breaks down and exudes goodness my comfrey is waiting below to absorb and accumulated greedily. Similar to your idea perhaps?

Pretty similar! - your comfrey will love the nutrients from your compost bin. I'm not sure whether I'll ever 'turn out' the inside of my comfrey circle and use the compost elswhere, it's more a way of disposing of green waste and converting weeds to safe mulch. Too many of my weeds will carry on groing if I just chop and drop, or hoe them off. The only risk I see with yours is if the comfrey roots invade your compost you could get some bits broken off and growing in there. I've got nettles around my compost bin and they're invading it! Nettles also love the extra nutrients from the maturing compost.

Nancy Reading wrote:Pretty similar! - your comfrey will love the nutrients from your compost bin. I'm not sure whether I'll ever 'turn out' the inside of my comfrey circle and use the compost elswhere, it's more a way of disposing of green waste and converting weeds to safe mulch. Too many of my weeds will carry on groing if I just chop and drop, or hoe them off. The only risk I see with yours is if the comfrey roots invade your compost you could get some bits broken off and growing in there. I've got nettles around my compost bin and they're invading it! Nettles also love the extra nutrients from the maturing compost.

I guess we are both converting garden  waste into comfrey leaves 😃. Im using my comfrey leaves to make comfrey tea which im using to feed my pumpkins. Interesting point you raise about the comfrey roots invading the compost.  Honestly you've got me wondering now could I harvest comfrey roots for some purpose 🤔

Johnny Shea wrote:Interesting point you raise about the comfrey roots invading the compost.  Honestly you've got me wondering now could I harvest comfrey roots for some purpose 🤔

I don't know whether they will, I'm just thinking like willow roots and drains and wondering.... Obviously you can you comfrey roots to propagate more comfrey. I know it has medicinal uses but I don't have experience of that. A quick search suggest tooth powder herefor example)

A comfrey circle is certainly something to try. Just make sure that you don't ever want to move that comfrey: Roots are very deep, and transplanting them would be hard. I'm just not sure the Johnson grass could not escape. They are the devil and will travel underground very far, and quite deep.
Comfrey gets nourishment from very deep roots, but  we do need to replenish their food: We cannot take, take, take, and expect consistent high returns.

I use comfrey as a grass block and it works quite well, i guess your invention will work. I do however add an extra layer of hay in front of the comfrey row in which i press potatos in spring. Maybe that could be a back up plan if the evil herbs escape!
It's great in a balm for tendinitis and muscle ache, arthritis like stuff. Grind 2 year old root down down add sunflower oil to it. Put it in a jar with lid and warm it to 40 degrees, let it sit for half an hour, strain and add rosemary lavender eucalypthus and whatever else is in pferdeselbe. It is too good, so they took out the comfrey in the commercial version.