En EspaŅol

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?

Share

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
1 rating

Friday - August 01, 2008

From: Bozeman, MT
Region: Rocky Mountain
Topic: Invasive Plants
Title: Wild mustard growing in disturbed ground in Montana
Answered by: Barbara Medford

QUESTION:

I have recently planted "plugs" of wildflowers in beds throughout my yard. Because the soil was disturbed, I now not only have some beautiful wildflowers growing, but also mustard plants growing in the wildflowers. And lots of them! Do I need to weed out the mustard plants this year? Or will they die back naturally and the wildflowers will take over next year? Will they compete with the wildflowers for moisture and light? Do I need to even worry about mustard plant invading my beautiful wildflowers? Thanks-

ANSWER:

First of all, it took us a while to discover just what plant wild mustard is. There are so many common names and synonyms for it that it was very confusing. However, we finally established that Sinapis arvensis is the common weed that is most likely infesting your garden. The first thing we want to say is YES, get rid of the mustard plants and do it quickly, because now is the time they are seeding out. They are very difficult to get rid of because they have establish a long-lived seed bank of their own. Pull them out and dispose of them so that their seeds will not spread. Apparently, they generally only show up in disturbed ground, as you pointed out, but although they are native to the Meditteranean area, they now show up all over the world, and appear in all states of the United States, including Hawaii and Alaska. They are classified as a noxious invasive in several western states. They are said to be poisonous to livestock once their seedpods are formed. Many of them harbor an eelworm that attacks other crops, therefore it is best not to grow them in a garden setting. In a word, they've got to go.

Wild mustard is considered a winter annual, which means it will bloom and seed in cool weather, but in Montana, it may very well do so in the Summer. See this website from the University of Missouri Extension on wild mustard.

The wild mustard not only will shade out and crowd out your other plants, but their seed distribution will only make the problem worse. They will not "die back naturally". They are annuals just as most of your wildflowers are, but you need to stop them before they seed. They are not altogether unattractive and if a few get by you and bloom next year, that's not a disaster. But don't let them seed.

Images of Sinapis arvensis.

 

More Invasive Plants Questions

Growing bluebonnets in England
June 08, 2008 - I'm sending some bluebonnet seeds to Norwich England to a dear friend. What time of year should she plant them?
view the full question and answer

Planting petunias around base of oak tree from Houma LA
March 30, 2013 - I live in south Louisiana and I want to plant petunias. Can I plant petunias around the base of an oak tree?
view the full question and answer

Getting rid of King Ranch bluestem
August 13, 2008 - I have recently moved to South Texas Coastal town of Portland, Texas. My St. Augestine turf grass has been invaded by - what the neighbors tell me - King Ranch Blue Stem grass. I am having a terribl...
view the full question and answer

Why is Asphodelus fistulosus (onionweed) forbidden by property owners assoications?
May 14, 2009 - Our local property owners association is imploring us to remove all onionweed (Asphodelus fistulosus L.). The USDA lists it as a noxious weed. Why? I think it is pretty and flowery. Is it poison...
view the full question and answer

Japanese Wineberry in Maryland
July 16, 2014 - Hello, we were at Cunningham Falls in Maryland and I can not identify this plant. If you could I would greatly appreciate it, thank you. It looks like a raspberry but the berries are inside small leav...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center