Sunday, April 21, 2013

Learn From My Mistakes: Crown Vetch

I probably ought to make this a series - heaven only knows that I've made plenty of mistakes over my time gardening.  Others might as well learn from my hard-headedness!

So, moving on to this particular example....  Last year I was cleaning out an area where a large Austrian pine had succumbed to pine wilt.  We had had the pine removed earlier last spring, leaving a large area that was bare of almost all vegetation and coated with pine needles.  This area was right next to the northeast corner of the house, so it seemed like a logical expansion for the front flower bed.

Of course, as is typical under a large evergreen, there were a few seedlings that had grown up from seeds dropped by birds, thoughtfully provided with a little bolus of fertilizer to help them establish.  We didn't want any large trees growing that close to the house, so removing the tree seedlings seemed straightforward.  However, as I started clearing out the stray clumps of grass and other plants that had managed to claim a spot, I found a small start of a beautiful, almost ferny, low growing plant that seemed to be acting as a groundcover.

Greg loves groundcovers and is constantly on the lookout for a particularly special one.  You know the type of plant he wants, the "perfect plant":  it will grow luxuriously enough that it outcompetes any weeds, never needs to be weeded, and forms a thick, lush cover, but it won't outgrow its space or choke out any wanted plants growing in or near it.  (Yeah, I know, an impossibility, oxymoronic in fact, but a gardener can dream, can't he?!)  I showed the plant to Greg and, indeed, he did like it, so I let it grow.

I hadn't identified the plant yet, but it had come in naturally and it was quite pretty - providing a ferny effect - but obviously very hardy and definitely providing good cover.  Neither of us were too concerned about leaving it for a while.  Eventually our mystery plant started blooming, and the blooms were attractive too.

In fact, the blooms allowed me to identify the plant as crown vetch (Coronilla varia).  I knew that this species was planted along highways and other roads for erosion control, and something was tickling my mind about it maybe being a problem in some way, but the Kansas Wildflower and Grasses page didn't raise any red flags for me.  The blooms only made it more attractive.  The plant seemed to be staying closely confined, so I let it be.  After all, the prairie environment is harsh enough that many "overly aggressive" plants elsewhere behave more reasonably for us.

Boy, was letting it alone a mistake.  By last fall, I'd decided that I really didn't want such a rapidly spreading groundcover in that spot, so I tried to dig it out.  Shortly after I thought I'd got it all out, I found new sprouts coming up all over the place.  By now, the plant was definitely spreading out widely and it was beginning to impinge on several small wildflowers I'd planted during the summer.  I dug out it all out again just before frost...and kept my fingers crossed over the winter.

I guess that finger-crossing isn't a particularly effective eradication technique. Wishing and hoping evidently don't work either.

I spent today doing my spring-time clean-up on that bed.  The crown vetch has now spread to an area about 6-8' in diameter.  Greg and I have decided it's time to pull out the Roundup, much as I dislike resorting to that option.  I trust that, by carefully using it, we'll be able to eradicate this infestation, but I sure wish I'd gotten rid of the crown vetch when I first realized it was developing as a "groundcover".  Live and learn.

My "live and let live" attitude towards unknown plants has served me well many times, but sometimes it reaches up and bites me.   This was one of those times.  I'd suggest getting rid of crown vetch immediately, if you ever find even a sprig of it in your garden.  A classic example of "Do as I say, not as I did!"

28 comments:

Karin / Southern Meadows said...

Sometimes it takes a whole growing season to identify a plant. Like you I am slow pulling something out until I know what it is because it may be a beneficial native plant. Live and learn! Thanks for sharing your experience.

greggo said...

I'm right there with you, I transplanted some bluestem and got three plugs of vetch. It is as bad as bindweed, if not worse. I tried digging it out this spring but I succumbed to Roundup also. Still have it...

Gardener on Sherlock Street said...

It sure is pretty, if that's all you want in the garden. Don't think I've battled this one yet. Yikes. I have to Roundup bindwind in places. Impossible to control otherwise. I hope you get it all right away.

Jason said...

Yup, before I got to your last two paragraphs I was thinking: Roundup. Not something we like to do but there are times there is no viable alternative.

ProfessorRoush said...

Yep, I hate the stuff for it's invasiveness. Roundup, you must. Principles be darned.

Melanie said...

Native four oclocks were the thing that I let live, not knowing what a pest they would eventually be!! Yikes!! Hope you can get rid of your vetch!!

Meredith/Great Stems said...

I'm familiar with that scenario -- letting something live until it can be identified properly. I'm sorry that in this case it turned out to be an invasive plant! I much prefer those happy surprises of a wonderful native "magically" appearing.

Tillie said...

I've made this mistake with:
- a tiny pretty clover
- ivy
- a type of lamium
- etc., etc.

Rose said...

I think we've all made this same mistake with one plant or another. The first time I read that burning bush could be invasive, I reacted with disbelief. But now that I have tons of little seedlings growing up in the flowerbed just in front of my large burning bushes, I understand. I can't use Round-up on that, but I sure would if I could!

When you find the perfect groundcover, let me know:)

Gaia, you asked if you could "pin" a couple of my photos from the Dallas Arboretum--you certainly may. In fact, after you asked, I pinned one of my favorite photos onto my board of plant ideas, too. Maybe next year I'll have my own pink tulips with purple and white pansies!

Gaia Gardener: said...

Rose, thank you for your permission to pin a couple of those photos - I had to laugh, because the pink tulips with the white and purple pansies was one of the ones I want to put on my "Plants to Purchase" and/or "Garden Design" boards on Pinterest!

And I'll be sure to let everyone know when I find that perfect groundcover! LOL!

Gaia Gardener: said...

Greg, I hope you'll let me know how your battle with crown vetch turns out! Roundup definitely seems to be making mine look less healthy, but we'll see if it actually does the job!

Gaia Gardener: said...

Melanie, 4 o'clocks could be a pain in Mobile (they develop huge tubers underground), but I didn't realize they could be a problem around here, too. Thanks for letting me know!

Gardener on Sherlock Street said...

Gaia,
I did a post once on the wild four o'clocks. I research what to do with them after my local extension agent ID'd them for me. Maybe some of my links can help:
http://gardenonsherlockstreet.blogspot.com/2011/05/wild-four-oclocks.html

Gaia Gardener: said...

Thank you, GonSS! I'm looking forward to learning whether or not you were able to get rid of the 4 o'clocks that you didn't want.

Gaia Gardener: said...

Thanks to everyone for the moral support! It would seem that this isn't an unusual problem....

Gardener on Sherlock Street said...

Well, they have not taken over everything. They did come up in a few surprising places so I suppose some seed escaped me. The drought probably helped keep them in check last year. I take after them with my garden shears now and then. We're coexisting pretty well.

Janet QueenofSeaford said...

We have vetch coming up around here too. Making an ID and then making the decision as to whether to leave the plant in question in place. In some spots I remove whatever comes in just because I want something else there.....other items live in my wild areas...totally unbothered by human hands.

Gaia Gardener: said...

Janet, even in "wild" areas, I wouldn't leave crown vetch, having experienced its ability to take over combined with how hard it is to get rid of. NOT a "plays well with others" sort of plant.

Indie said...

I am also a 'wait and see if the weed turns into a wildflower' type of person. Oftentimes, even after identifying a plant as a wildflower and loving it, they become much too robust for the garden beds! I hope you can get rid of your overly-boistorous ground cover without too much trouble!

Gaia Gardener: said...

Indie, I love your use of the words, "robust" and "overly-boisterous"! Perfect descriptors! (I've also seen "assertive" used, but I like your adjectives better.)

badasin22 said...

I picked up crown vetch as a perennial at the nursery. The tag looked like it was cute and compact. I took it home and merrily planted it in three spots. By autumn...Woe is me! Why would they sell that stuff????? What an uber huge mistake!

Gaia Gardener: said...

Badasin22, I have NO idea why any reputable nursery would sell the stuff, at least without a warning label about its aggressive nature.

We've had reasonable success dabbing the crown vetch with old-fashioned Roundup (not the newer, "quick kill", varieties which can transfer root to root to nontarget plants). It's taking multiple treatments, but the crown vetch is definitely declining with each treatment.

Anonymous said...

I love my crown vetch... It grows beside my back alley below and beside a 40' row of Honeysuckle bushes. I have had no problem with it being invasive. Bordered by the alley, driveway and a sidewalk it has nowhere to go. Guess it doesn't like the shade under the bushes, so doesn't go in that direction either. Before I planted it about 15 years ago, that area was full of weeds and nothing else. So, guess I am one of the few people that can really appreciate it.

Anonymous said...

Even if the crown vetch has nowhere to go, birds or other animals can transfer it. I came back from vacation and the vetch had spread to my little vegetable garden. It grows like crazy here in the interior of Alaska.

PlanetClaire said...

Major déjàvu reading this post!! I could make oodles of loot selling Crown Vetch....but would feel TERRIBLE to plague anyone else with the nightmare I have endured over the past four years to eradicate this stuff!! I have tried everything short of burning down the garden to get rid of this well named plant. Crown vetch is a royal pain in the ....knees, back, neck, shoulders...you get the idea. Please let us know how you solved your in-vetch-station! Best of luck to us all!

Gaia Gardener: said...

PlanetClaire, I DID get rid of it, basically through simply digging out the roots, over and over again. I am so glad that it hadn't spread any further than it already had, because it took a lot of effort to get rid of it. Good luck! And thanks for stopping by.....

Unknown said...

When we purchased our home, we discovered crown vetch was planted on both the back and front slopes as a ground cover. I hated how it looked - so weedy. Not wanting to resort to chemicals, I pulled it out and covered the entire hill with yard fabric and mulch. It looks nice, but any uncovered area has sprigs of Vetch growing. Hate it! We tried RoundUp then, which killed it along with the bushes the Vetch was covering. Sadly though, the following Spring, Vetch is back after spray. Terrible!! I'm not sure I'll win this battle ever.

Gaia Gardener: said...

Ouch, that's painful. Good luck. I did finally win the battle, but I was only trying to get rid of a small patch, not a large area. I don't envy you the struggle.