Garden Myths - Learn the truth about gardening

Invasive Plants You Should NOT Buy

You are at the nursery and have found a nice looking plant. Is it safe to bring home? Your friend has some extra plants and offers to give you some – should you take them? In both cases you can get into a lot of trouble by taking the plant home.

This is a list of invasive plants you should never, never, never add to your garden–unless you want them everywhere.

Nurseries should be restricted from selling them to unsuspecting customers.

What is an Invasive Plant?

An invasive plant has two common characteristics. It spreads fairly quickly either by seeds or a running root system. Secondly, the root system is near impossible to remove. Any small bit of root left in the soil will grow again.

This is by no means an exhaustive list, but it does contain some of the worst of the worst. I have struggled with almost all of them.

As one of the commenters below points out, invasiveness is regional. Something that may be invasive in zone 5 may not grow in zone 8, for all kinds of environmental reasons. This list of plants is invasive in zone 5, Ontario, in clay-type soil, and probably most of Northeastern North America.

 Goutweed (Aegopodium podagraria)

Goutweed (Aegopodium podagraria)

Goutweed (Aegopodium podagraria)

 Lily-of-the-Valley (Convallaria majalis)  

Lily-of-the-Valley (Convallaria majalis)

Lily-of-the-Valley (Convallaria majalis)

 Chameleon Plant (Houttuynia cordata)

Chameleon Plant (Houttuynia cordata)

Chameleon Plant (Houttuynia cordata)

 Ribbon Grass (Phalaris arundinacea)

Ribbon Grass (Phalaris arundinacea)

Ribbon Grass (Phalaris arundinacea)

Periwinkle (Vinca minor)

Periwinkle (Vinca minor)

Periwinkle (Vinca minor)

Mint (Metha species)

Mint (Metha species)

Mint (Metha species)

 Sedum acre

Sedum acre

Sedum acre

 Lyme Grass (Leymus arenarius)

Lyme Grass (Leymus arenarius)

Lyme Grass (Leymus arenarius)

 Running Bamboo

Running Bamboo

Running Bamboo

 Bell Flower (Campanula punctata)

Bell Flower (Campanula punctata)

Bell Flower (Campanula punctata)

 References:

1) Goutweed (Aegopodium podagraria) Photo: Funki Sock Munki

2) Lily-of-the-Valley (Convallaria majalis) Photo: yamaken

3) Chameleon Plant (Houttuynia cordata) Photo: Sunchild57 Photography.

4) Ribbon Grass (Phalaris arundinacea) Photo: Learn to Grow

5) Periwinkle (Vinca minor) Photo: Patrick Standish

6) Mint (Metha species) Photo: Kham Tran

7) Sedum acre Photo: Sólveig Zophoníasdóttir

8) Lyme Grass (Leymus arenarius)Photo: Thompson & Morgan

9) Running Bamboo Photo: Heather Bailey

10) Bell Flower (Campanula punctata) Photo: Qwen Wan

Robert Pavlis
Editor of GardenMyths.com
I live in southern Ontario, Canada, zone 5 and have been gardening a long time. Besides writing and speaking about gardening, I own and operate a 6 acre private garden called Aspen Grove Gardens which now has over 3,000 perennials, grasses, shrubs and trees. Yes--I am a plantaholic!

I hope you find Garden Myths an educational site that helps you understand your garden better.

17 Responses to 'Invasive Plants You Should NOT Buy'

  1. Jamie says:

    Houttuynia cordata chameleon Is a nightmare. We were warned it was invasive, but we had no idea. I hate the thought of roundup, but I may not have a lot of choice. I like the paintbrush idea. Last year we took a tiller to it. I think every tiny piece regrew! Ugh.

  2. beahsmith says:

    Florida betony is spreading rapidly for me even though I pull it up by hand and spray with roundup (maybe not strong enough a dose–I use 6oz to a gallon of water).

  3. Robin Bickel says:

    While Campanula puncata is a definite thug that I would never plant, people should be aware that there are lots of beautiful Campanula species that are definitely garden worthy. I currently grow 6 different types and all are well behaved.

  4. Depending on its location, spotted dead nettle (Lamium maculatum) can easily become invasive. As can yellow archangel (Lamium galeobdolon). I learned that the hard way 🙂

  5. Bonnie says:

    I have a patch of polygonatum (Solomon’s Seal) which has taken over an entire flowerbed, totally choking out the columbines and Bleeding Hearts that were there. Every year, rhizomes make their way under the edging and wind up in the lawn, where I yank them out. It’s coming up on a vigorous patch of bletilla striata now. It’ll be interesting to see which wins. I love the polygonatum–and hate it. In a prepared flowerbed it is a nightmare. On the edges of woods where nothing else is growing, it’s tough, durable, and attractive.

    • All plants compete for space, and the stronger ones survive. It is quite common to have plants that need to be corralled by gardeners.

      You either need to keep on top of them, or move them to a less hospitable location. They can be quite dry, and then they don’t spread as much.

  6. Art Thompson says:

    I’ve been killing a patch of mint all summer that I started 7 years ago. Still haven’t got it all.
    If I want mint for Mojitos, I’ll grow it in a pot.

  7. Sally Waid says:

    Why are we so neurotic about beautiful plants. I wish I could grow the beautiful Lily of the Valley in my hot climate. Mint is a useful herb
    herb and can be easily contained!

    • I had some lily of the valley and got rid of the clump. I am now finding clumps in my woods that can only be there through seeds. I know of several native places that are now fully covered with this weed.

      Thought I would try some mint too – that was 5 years ago, and only left it in the ground for 1/2 the summer. I have worked hard at ridding it, but it is still showing up in my iris even though I pull every piece I see.

  8. Katie says:

    A great way to get rid of Houttuynia once it has started growing into other plants is to take a 1 gallon black plastic pot and cut the bottom out. You can use this to encircle the stems of the Houttuynia and then spray with RoundUp without harming nearby plants. I credit my buddy Mary for coming up with this solution.

    Katie in Illinois

  9. Fiona Richards says:

    I am in the process of trying to get rid of the Chameleon plant by digging it up, but some places I can’t get to. How did you get rid of your plants?
    Thanks

  10. Leslie says:

    I think whether something is “invasive” or not is dependent on local conditions. Along Colorado’s front range, yarrow can take over in short order and myrtle spurge (Euphorbia myrsinites) is listed as “Noxious” by many counties. But vinca doesn’t do very well out here; it will sometimes make a passable shade ground cover, but I don’t see it get out of control and municipalities don’t list it as a problem.

    • You are absolutely right. I was in Colorado 2 years ago and got a chuckle out of the signs saying myrtle spurge (Euphorbia myrsinites) was invasive. Here it does spread a bit, but I’d hardly call it invasive. I have never seen it outside a garden.

  11. Carol Clark says:

    #11 – Scilla sibirica – a welcome sea of blue in March turns into a horrible mess of prostrate leaves which hang on for 2 months. Never let them go to seed in a perennial garden!

Please let me know what you think - Leave a Reply