Invasive Plant - Ask Extension
Hi there,
I’m a local gardener and I have a client who has a large garden filled with Houttuynia. I’m wondering what is the best way to complet...
Knowledgebase
Invasive Plant #813261
Asked October 05, 2022, 12:09 PM EDT
Hi there,
I’m a local gardener and I have a client who has a large garden filled with Houttuynia. I’m wondering what is the best way to completely get rid of it. It’s too large of an area to dig out by hand. She also has a dog and grandkids, so we would prefer not to use chemicals. I was thinking black plastic, but I’ve read online from other people that it didn’t help. Other thought was to get a bucket loader and completely dig out the entire garden and dispose of the soil. Hoping to get some insight and suggestions.
Thank you!
Lamoille County Vermont
Expert Response
Hi, Mary. It sounds like you've done some ID work on Houttunyia already. (If you want confirmation of your ID, send us a couple of photos.) I'm personally not familiar with the plant, but I have been researching it and the results are not encouraging. Here is an article that includes both information and the story of another gardener's battle with this plant! https://www.ecolandscaping.org/06/landscape-challenges/invasive-plants/after-a-20-year-dormancy-it-raised-its-ugly-head/
Houttunyia is very hard to get rid of because it spreads aggressively by rhizomes. Be careful if trying to dig it up, as bits and pieces of broken rhizomes will sprout into new plants.
You can try to contain it by managing the borders as proposed by this website: "Start at the outer edges of the patch, digging about 2 feet (0.5 m.) outside of the visible foliage and stems. Remove rhizomes as you find them and bag them. Dig down at least 12 inches (30.5 cm.). It is useful to have a large tarp handy to place shovels full of soil and sift through for pieces of rhizome, leaves, or stems. Take sifted soil and store it in another part of the garden. Once you have gone through the entire bed, you can return the “cleaned” soil. Keep an eye on the area and remove any plants that sprout. You may have to do the entire process again for the next season or two."
You can try black plastic as per this recommendation: https://www.torontomastergardeners.ca/askagardener/eradicating-houttuynia-cordata-chameleon-fish-mint/ .
If you are contemplating removing all the current soil, consider how you would dispose of the "contaminated" soil!
Whatever approach you take, expect it to be a long process. Let me know if I can help any further.
Houttunyia is very hard to get rid of because it spreads aggressively by rhizomes. Be careful if trying to dig it up, as bits and pieces of broken rhizomes will sprout into new plants.
You can try to contain it by managing the borders as proposed by this website: "Start at the outer edges of the patch, digging about 2 feet (0.5 m.) outside of the visible foliage and stems. Remove rhizomes as you find them and bag them. Dig down at least 12 inches (30.5 cm.). It is useful to have a large tarp handy to place shovels full of soil and sift through for pieces of rhizome, leaves, or stems. Take sifted soil and store it in another part of the garden. Once you have gone through the entire bed, you can return the “cleaned” soil. Keep an eye on the area and remove any plants that sprout. You may have to do the entire process again for the next season or two."
You can try black plastic as per this recommendation: https://www.torontomastergardeners.ca/askagardener/eradicating-houttuynia-cordata-chameleon-fish-mint/ .
If you are contemplating removing all the current soil, consider how you would dispose of the "contaminated" soil!
Whatever approach you take, expect it to be a long process. Let me know if I can help any further.
