Wednesday, April 27, 2011

Warfare in the Garden - Moving Comfrey


In which our heroine attempts to eradicate well established comfrey plants which are tragically misplaced in the garden.

Everyone makes mistakes when they start gardening.  Putting comfrey plants at what I thought were going to be the corners of the garden was one of mine.  The garden has expanded twice since those plantings, and two comfrey plants are now positioned where I've decided there should be pathways.  Comfrey is legendarily difficult of removal, and these plants seem to find their current locations quite agreeable. 

I have a method to my madness, or so it pleases me to think.  I've had a few years to observe the way comfrey grows, and how other plants behave around it.  I've noticed that:
  • comfrey leafs out early in the spring
  • comfrey dies back late in the fall
  • one comfrey plant generally gets to about 3.5' (~1.1m) in diameter
  • nothing - I mean no plant - grows under the full shade of an established comfrey plant
As a homesteader, and a frugal person, I've gotten into the habit of asking myself, about most anything, "What's it good for?  What can I do with it?  How could it be repurposed to serve my needs?"  Naturally I ask, what's comfrey good for - in a structural, functional sense within the garden?  (Because I'm already up to speed on all the other fabulous stuff it's good for.)  It seems to me that comfrey could well form a low hedge plant, to hold back the crab grass from the borders of the garden.  Since comfrey is around both early and late, the grass shouldn't be able to get a leg up.  Another tool in comfrey's campaign for supremacy is its habit of plastering the ground with all the foliage of the year when it dies back in the fall.  Nothing comes up through those layers of leaves before the new comfrey shoots of spring are well on their way.


So the first step in eradicating the comfrey was to take divisions of the roots and transplant them to the northern end of the garden.  This area was heavily lasagna mulched in fall of 2009.  The mulch did a decent job of holding the weeds in check all through last year.  But as you can see, it would need renewal this year to keep the weeds back.  I'd much rather create a self-maintaining border composed of a plant so profoundly useful, and not ever have to give that area another lick of work. With the help of our first WWOOF volunteers of the year, I took some dormant root pieces and stuck them in small holes in the unimproved soil at the garden's edge back in late February, spaced roughly 3.5' apart.  I did absolutely nothing to help these roots along, and after watching for about a month I only needed to put in second root divisions at two of the transplant locations.  I now have obviously viable comfrey plants at each of the ten orange flags in the picture above.  I may expand the comfrey hedge along the western edge of the garden at some point.

Aside from getting rid of comfrey plants where I no longer want them, relocating comfrey seems to make good sense from a fertility perspective.  I think of comfrey as a miner plant.  It grows a formidable taproot and pulls up nutrients from deep underground, making them available to more shallowly rooted plants.  But every mine plays out eventually.  These comfrey plants have been in place for four years.  Putting new plants in a new area should grant access to untapped resources.  Comfrey is also a plant with an extraordinarily large surface area for its size.  The leaves are very broad and long, while the stems are minimal.  I don't know this for a certainty, but that would seem to suggest that comfrey transpires a lot of water vapor, well supplied by its tap root even when the soil surface is relatively dry.  In times of drought that moisture would be helpful to other plants nearby.  At the same time, by covering so much soil, comfrey regulates temperature and slows water loss from the soil through evaporation.  Even if I'm wrong about comfrey's utility to nearby plants, establishing an entire row of these plants where nothing but grass was growing before seems like a good idea.  It will store carbon in the soil, provide more food for bumblebees, and serve as convenient a trap crop for Japanese beetles, making them easy to handpick for the hens.

So much for all the benefits of moving the plants.  But how do I imagine I'll eradicate the comfrey from its current location?  Well, I plan to take a multi-pronged and long term approach.  And to be philosophical about it, rather than allowing my personal feelings to come into it.  Now that I know the root divisions have taken, I'll basically just keep cutting back the growth of the parent plants.  I expect to take at least six cuttings this year, and I don't expect to win the war in one year.  The first spring cuttings from the comfrey will, as usual, be used to provide some extra fertility to the potatoes when I plant them.  This year I may also use comfrey cuttings to give the corn a boost as well.  After that, I'll take several cuttings to dry for the chickens' winter feed, and also feed it to them fresh.  I will even let them have direct access to the comfrey occasionally so that they can do some damage on their own; although I know they'll be far more interested in eating all the critters living below the mulch that the comfrey creates from its own leaves.  The damage to the comfrey itself will be purely collateral.  Other than that, I'll just keep cutting back the top growth of the plants, so that the roots gradually deplete themselves.  Without leaves to photosynthesize, the roots will eventually starve and die.

Depending on how it goes, I may experiment with solarizing the root mass at some point.  This would entail covering it with clear plastic and weighting down the edges so that the roots are both deprived of water and baked by the sun.  It sounds torturous, I know.  The only thing that salves my conscience is knowing that I've already provided for the continuation of the plant's genetic line.

Tune in later this year to see how fares the war.  And wish me luck.

19 comments:

Paula said...

Good Luck.

I'm trying to get comfrey seeds to take in a couple of places in the backyard, but so far, no luck. I want it for the compost pile, and I've read that comfrey leaves make good toilet paper in a pinch....

I'm also trying to get nettle seeds to take and borage too. Who in their right mind would plant all these weeds?

Someone who doesn't consider them weeds, that's who.

I will be watching this space to see how you do!

Andrea G. said...

I can't help but be reminded of the response of a landscaper to a potential client who told her, "I have bamboo and mint in my yard, and I don't want them any more." Her advice was "Move."

May you have better luck!

saving for travel said...

We mix our comfrey up with foxgloves in our garden. Until they flower of course. :)

Sft x

Hazel said...

Ooo, Paula! Comfrey TP sounds a bit...prickly!

I use borage like comfrey, mostly as mulch or in the compost heap.

I like the idea of comfrey as a hedge. I wonder if I could plant it alongside my strawberries? It might cut down on a bit of weeding, as long as I make sure they're not shaded...

Devouring the Seasons said...

What an amazingly informative post! We have some comfrey in our yard, but haven't really put it to good use yet. I will definitely take advantage of your wealth of information when deciding what to do when it's time deal with our own comfrey. Thank you! :)

Kate said...

Paula, I'm hoping to propagate more nettles this year too. Some comfrey produces only sterile seeds. So I hope that's not what you're trying with. Root divisions seem to be the way to go with the Bocking varieties. As for TP, as Hazel says, it gets fairly prickly as the leaves get larger. Might work this time of year when the leaves are small, but it wouldn't answer most of the time as TP replacement.

Andrea, too funny. I have patience for the project. I hope that will answer in place of luck.

SFT, I've heard that other people mistake these plants too. To me they look quite distinct. Perhaps it's the pruned woody stalks still sticking up among the foxglove from last year's blooms.

Hazel if you try comfrey as a hedge, just be sure you're giving it the space to expand that it's going to take up. Strawberries wouldn't stand a chance if planted to close to comfrey. Please let me know how it goes for you if you try it.

DtS, you're welcome. If you haven't already done so, click the link in this post regarding comfrey's other uses. It really is an amazing plant; certainly one of the most important on my homestead.

Tamar@StarvingofftheLand said...

Kate, if you need reinforcements, my brigade of chickens will cover your eastern flank. They are guaranteed to eat it down to the stumps.

Kate said...

Tamar, huh... My hens like comfrey in moderation, but I would never expect them to eat every last bit of it. They definitely seem to prefer variety in the greens department. Sow bugs, on the other hand, they will gobble until the sun goes down.

agwh said...

I have no doubt that you will be able to re-establish the Comfrey where you want it to grow now, but getting rid of the old plant completely could take awhile.

At the Plant-a-Row-for-the-Hungry garden where I volunteer, we have a patch that we have been trying to remove (from the middle of the garden!) for four years now.

We dig it up, but there must be an incredible root WAY down deep that we are missing, because it just keeps coming back up.

Dmarie said...

my mistake was planting mint anywhere except in a container!

Sandy said...

Kate, I have ramps and watercress for you but I've misplaced your number. Sandy (610-216-4233)

Anonymous said...

I have read that to remove comfrey or other plants such as mint try the smothering idea. Weed barrier plastics or cardboard etc, covered with mulch of choice. I killed an entire patch of english ivy that had over grown a 20 x 20 area.

Ilene said...

I sure wish I lived close enough to you where I could get a start of that comfrey from you! I've been trying to start it from seed for three years now without success. So far haven't been able to find anyone local (NE OK) to me that grows it.

Love your informative posts.

Kate said...

Anon, the smothering technique is certainly one I would consider if my present methods don't work. I have a feeling that this early in the campaign the comfrey would simply push up a barrier unless it was very heavily weighted, and try its best to work around anything that was heavily weighted.

Ilene, you'd be welcome to as much of it as you liked. You might want to check and make sure that the seed you're trying to start isn't from one of the sterile varieties of comfrey. That would be an exercise in futility. And if it's *not* a sterile-seeded variety, and you *do* ever get it started, watch out! I wouldn't want a comfrey plant around that was capable of propagating itself far and wide.

Summersweet Farm said...

Wonderful information. I just planted my first comfrey this year, in the mini-orchard, in the hopes that some year I'll be able to fence that whole area off in the Fall as chicken quarters; in the mean time the comfrey can fertilize and be friendly to the fruit trees. :)

Fransene said...

If we want an orchard with geese living in it, how will that affect the growth of comfrey planted near the fruit trees?

CSH said...

I have a Comfrey plant about three feet from a Maple tree. The tree's leaves were late to come out and are very pale. My husband thinks the Comfrey is toxic to the tree. There is a second Maple about 6 feet from the first Maple and it has healthy green leaves. Do you think the Comfrey is the problem?
Sue

Kate said...

CSH, I've never heard of comfrey harming any plant around it. It is commonly known to help other plants and fruit trees in particular. My guess is that there's something else wrong with that maple tree.

Anonymous said...

I'm very interested in your experiment of getting rid of the comfrey. I made the mistake (2-3x) of trying to dig comfrey out, once to replant elsewhere. Now I have too much and in multiple places. I did kill some by putting a compost bin on top of it from summer through spring. Now I have to figure out the others.

I haven't heard that some comfrey seeds are sterile before. Do you know how to tell which ones?
dcg