g'day maureen,

in the right conditions that is good moisture and reasonable soil, comfry will take over for sure, and it will be hard to erradicate not impossible but hard. i grew it around fruit trees in a very sandy loam situation with medium/low rainfall so it copped dry periods and then frost which all kept it growing slow, some actually died from the dry.

so for the main it is best grown in an area where it can be contained to some degree, yes it is a very useful plant in pc but then so is any other weed which can be more controlable.

len

Here is a link that might be useful: lens garden page

I love growing comfrey! I make comfrey tea for the garden (fermented for a few days), since the comfrey mines the soil and brings up minerals. I think the key to controlling it is to use it. In northern Calif., at least, it can be cut back 3 or 4 times a year. I have been growing it for 2-3 years at the edges of my garden and next to the compost bins, and it has not spread, but I do cut it back often and use it either for garden tea or directly on the compost pile.

Comfrey spreads by roots. It is possible to plant comfrey from root pieces -- a three-inch section is all you need. But if you want to dig it up, you will never get all the root pieces. My permaculture teacher says it can be eradicated by deep, persistent mulching.

An easier to manage plant is borage. It's a self-seeding annual with edible blue flowers and makes a wonderful border, though it does get mangy after a while. I dig up seedlings if I want a plant in a certain spot, and within a few weeks I have another huge plant, up to 3 feet high. The bees love it -- it's a great plant to draw pollinators to the garden.

I also use yarrows to encourage pollinators and beneficial insects. The yellow yarrow (Moonlight) spreads even with little water, but it is easy to dig up. I divided one clump into 24 plants a year or so ago, then I gave away a bunch of those after they had grown big, and I still have a wealth of yarrow.

ok, great suggestions, GardenLen and Habitat. I have yarrow in the yard and borage seeds in the pack, will move the yarrow and plant the seeds. I'll also divide and plant more comfrey today, for I can always cut it and throw it in the compost bins. I'll cut some, too, for some tea.
GardenLen, the comfrey is now in good soil, but I'll move lots of it to poorer, sandy soil, where it may not thrive so well but will benefit its locale.
Thanks! Maureen

yes maureen,

the sandier soil will control is rampant abiltity to spread, we had it growing in very sandy loam, and found if it got no water at all it would very quickly die out or its growth could be limited, but it was doing the job it was there to do. and that was to send its roots very deep and drag up all those nutrients.

len