Host an Event Volunteer Join Tickets

Support the plant database you love!

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
2 ratings

Sunday - March 20, 2011

From: Muskogee, OK
Region: Southwest
Topic: Non-Natives
Title: How to eradicate non-native invasive Houttuynia cordata from Muskogee OK
Answered by: Barbara Medford

QUESTION:

I have planted a very invasive plant called houttuynia and cannot get rid of it! It is very stinky and the stems break off easily at the roots. I cannot dig it up anymore - it is all over in my flower bed! Do you know of something I can spray on it to eradicate it - and not kill my other flowers!?

ANSWER:

Since this plant is native to southeast Asia, we have no information on it in our Native Plant Database. However, we are always interested in controlling or eliminating invasive plants, native or not. From a website by Ohio State University, we found this article on Houttuynia cordata, which indicates, among other things, that is is invasive because it spreads by underground rhizomes which, even if a small fraction is left in the soil, can still continue propagating. A wonderful argument for investigating the habits and nativity of any plant before you plant it.

Please, no spray! One of the things you will learn when you read the above link is that it seems to be resistant to many herbicides. We have a more or less standard operation that we suggest for trying (notice we said trying) to control invasive plants. Any spray you try will probably not faze the invasive, but will lay waste to all the broadleaf plants around, including your ornamentals. Buy some wide-spectrum herbicide and some small sponge disposable paintbrushes. Clip off every stem you can find emerging from the soil and then, quickly, within 5 minutes, paint the cut stub with the undiluted herbicide. You must do this right away because the stem will quickly begin to heal over to protect the rhizomes beneath. Of course, don't allow the plant to bloom and keep all leaves cut off in order to deny those rhizomes of the food they get from the leaves. Theoretically, in a perfect world, that would cause the rhizomes to starve to death. However, the way that plant became so invasive is by being very tough and adaptive, so you can't let up. Apparently, the plant is somewhat dormant in the winter, so that would be a good time to really make a digging assault on the rhizomes and be sure to dispose them where they won't root again! But you must persist and keep after the plant, constantly looking for sprouts in places you didn't expect it to be.

 

More Non-Natives Questions

Disease problems with non-native Globe Willow
May 23, 2009 - Globe Willow - Is exuding a white frothy foam/sap at several locations. What is this and how can it be stopped?
view the full question and answer

Non-native. Why are my potted Royal Empress trees dying?
June 22, 2009 - I have purchased several Royal Empress trees over the past two years. Why won't they grow? Some sprouted leaves and then died while in the pots I planted them in. While others, that are 2 years old ...
view the full question and answer

Dying non-native St. Augustine grass from Austin
May 02, 2013 - Although we all know St. Augustine grass is not a good thing, I am stuck with it and am trying to save areas that appear to have take-all fungus. I have done much reading online and have tried peat m...
view the full question and answer

Pruning Cuphea Plants
February 04, 2013 - The David Verity cuphea (cigar plants) that I planted last spring are now 3-4 feet high. I would like to move them, but before I do they seem to need pruning. All the branches are brown and dry lookin...
view the full question and answer

Non-native, invasive peanut butter tree from Canby, OR
July 17, 2012 - I too have a peanut butter tree with the pink and white blooms, its about 5 years old and is beautiful, but 2 weeks ago it started wilting and losing all its leaves, I am afraid it is dying. Can I sav...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.