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linnea56chgo5b

Best way to kill off garlic mustard?

IâÂÂve had it in one section of my garden for as long as I can remember. ItâÂÂs never allowed to go to seed. I pull it as soon as its big enough to grasp. But (as you probably know) it just breaks off at the soil line, and soon leafs out again.

Now I have something I want to plant there. (A large hosta) But I donâÂÂt want to deal with this coming up around a major plant.

I tried spraying it with Round-up yesterday, and can see no difference! I donâÂÂt know how fast it works, though.

Is Round-up the best approach, or should I try smothering it with wet newspaper and mulch? ThatâÂÂs what I use to kill grass before digging a new bed. If the latter, how long is long enough? IâÂÂve only done it over the winter. Thanks!

Comments (19)

  • lisanti07028
    10 years ago

    Dig it up. Use a ptichfork if it's too near another plant.

  • mad_gallica (z5 Eastern NY)
    10 years ago

    It has a shallow root system so it isn't too hard to get.

  • susanzone5 (NY)
    10 years ago

    It's easy to pull up by the roots. Roundup takes a week or more to show signs of dying.

  • terrene
    10 years ago

    Garlic mustard is a biennial so I'm surprised it hasn't died away, since you never allow it to set seed. It is easy to pull up, but if there is a lot of it I have used generic glyphosate. It does take some time to show the dieback.

    This is one plant I try to jump on when I see them, regardless there are usually a few plants that try to get started here and there. The seeds probably come in on the bags of leaves or grass clipping I collect at the compost site, or they could hitchhike on a dog, deer, or my pant leg.

    It's a bummer to see this plant colonizing the roadsides and along trails around here. It's covering the floor of some of the woodlands at the nearby Minuteman National Park (where the colonists fought the British during the Revolutionary War). It's so invasive.

  • marquest
    10 years ago

    I do not let it flower. It grows one year, flower the next year. If you pull it before it flowers you should be able remove most of it but you it will probably never be all gone. 3 years later I still see one or two coming up here and there.

    I think roundup is a fertilizer they have watered it down so much. I use vinegar mixed with salt.

  • docmom_gw
    10 years ago

    I've been doing lots of research on this problem. It sounds like the best way to control garlic mustard is to spray a RoundUp type product early in the spring. Garlic mustard is evergreen, so it is visible and susceptible to herbicides before native woodland plants have broken dormancy. So, spray early, pull any plants that find a way to bloom, and continue to monitor areas that have been infested for many years. The seeds can remain in the soil for up to thirty years, according to one article. Disturbing the soil can bring seeds to the surface that have been hiding out, awaiting their chance to sprout.

    Martha

  • linnea56 (zone 5b Chicago)
    Original Author
    10 years ago

    Thanks! I know it has been coming up in this area for at least 10 years. I have never been able to plant anything (successfully) there, as it gets so tedious to pull it out of a perennial. I think it came in originally in a load of topsoil.

    Vinegar and salt, interesting, marquest. Just straight white vinegar? How much salt? I'd like to try that on the grass popping up between my patio blocks. .

  • marquest
    10 years ago

    Here is the recipe.

    But what I do is keep a squirt bottle with me when I walk the gardens with white vinegar, and 5 tablespoons of salt. I use it in my walkway, on any weed coming up between the bricks and my never ending poison ivy.

    Here is a link that might be useful: Weed Killer

  • terrene
    10 years ago

    From what I've read about "natural" herbicides, household vinegar is not strong enough to kill weeds by itself, and the industrial strength is very caustic and requires protective wear. Also, that salt will contaminate the soil making it infertile for many years??

    Glyphosate, the active ingredient in Roundup, is relatively benign and breaks down when it contacts the soil (however in should not be sprayed in wetlands, because the surfactant is toxic to aquatic life).

    The patent on Glyphosate expired over 10 years ago, so generic is available much more cheaply than the "Roundup" brand. Not to mention Monsanto sux. I bought a large bottle of concentrate called Kleenup online.

    The best time to spray, pull or weed whack Garlic mustard is in the early Spring before it is sending up the flowering shoots. As docmom said, it is easy to spot the evergreen clumps before native plants have emerged. Once it flowers it should be bagged and disposed of, because it has the ability to set seed after it's pulled.

    I pulled a bunch at my rental house a couple weeks ago, and they're sitting in a plastic bag getting baked in the sun. I'm hoping to bake the flowers so that it doesn't set seed and be able to compost the plants, rather than put them into the waste stream.

  • diggerdee zone 6 CT
    10 years ago

    I use the vinegar, but only with a teaspoon of salt per spray bottle (I think 28 or 30 ounces??) - I was afraid much more salt would clog the sprayer, to be honest, lol. I do have to apply several times, but I would never use Roundup.

    For the garlic mustard in particular, I usually just pull it. For my particular experience, it is usually along the edges of the yard, under the woodland edges, etc., and the soil is very loose there - sometimes the GM actually seems to be rooted only in leaves! So it is easy to pull in that situation. I haven't had to deal with it in many other situations so it may be harder.

    I always wonder - if it's in flower, and I pull it, and I throw it in the woods, will the seeds still form and then reseed? Am I shooting myself in the foot by throwing the flower heads into the woods...?

    Dee

  • marquest
    10 years ago

    Yes you are shooting myself in the foot. With my bottle of vinegar I carry a bag and all weeds pulled go in the bag. If you throw them in the woods it is moist shady they will continue to grow and make seeds. All they need is a little moisture to continue to develop and seed.

  • diggerdee zone 6 CT
    10 years ago

    Sigh.... nothing's ever easy, is it?

    :)
    Dee

  • marquest
    10 years ago

    Nope,

  • naturemitch
    10 years ago

    Keep pulling the plants. Using chemicals is only going to get rid of current leafy growth/plant....you are not touching the seed bed. If cutting blooms, cut them early enough so seeds have not formed.

    If the patch isn't too big, I would opt to manually remove the plants. We use hand removal methods on pretty good sized patches and you will see a decrease in density over time.

    good luck.

  • docmom_gw
    10 years ago

    I am as anti chemical as anyone, but there comes a point when hand pulling just won't work. I have a large wooded/wetland area behind my property that backs up to the interstate. So, it doesn't belong to anyone, really. Well, there are probably over 20 acres of untended land, and there are patches of garlic mustard scattered throughout the entire area. I tried to pull some of the patches closest to my yard, but after six hours on each of three Saturdays, I still had another three Saturdays' worth just in view of my house. I have better things to do with every Saturday in May for the next countless years than pull garlic mustard. I bought myself a pump sprayer of glyphosate and attacked my Lily of thr Valley. The speed with which I can treat a large bed, and know the roots are dead, is truly liberating. I can now look into the future and see newly planted native flowers and understory trees and shrubs instead of growing beds of garlic mustard.

    Martha

  • coolplantsguy
    10 years ago

    Some detailed info...

    Here is a link that might be useful: Control Methods for the Invasive Plant Garlic Mustard

  • NHBabs z4b-5a NH
    10 years ago

    I used to try to control it in one garden in my mom's yard where it had come in on soil. She had clay soil, so often the root broke off if just pulled. I would go out when the soil was moist with an old screw driver or hand dandelion puller to get the roots. The I would put down corrugated cardboard and cover that with a layer of mulch. Sometimes I would also use corn gluten. While it did not get rid of it entirely, doing this once a year when I visited kept it from spreading

  • Marie Tulin
    10 years ago

    Of note in the summary of the article is that hand cutting the stems (using a weedwacker) and spraying roundup are the most effective routes of containment of large investation.
    If you've received a lot rain recently, it is a good time to tackle garlic mustard removal, because the plants will be putting out flowers = seed.
    It is well worth reading the entire article. It is sobering, but good control can be had for those who are persistent and understand the plant's life cycle.

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