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
Not Yet Rated

Tuesday - November 26, 2013

From: Dripping Springs, TX
Region: Southwest
Topic: Invasive Plants, Non-Natives
Title: Advisability of growing Silybum marianum (Milk thistle)
Answered by: Nan Hampton

QUESTION:

I just received a load of clay-mix-dirt - and after our recent rains noticed the pile sprouting what looks like "Milk Thistle." Lots of them. The leaves are spiny and variegated - quite pretty. I was thinking I might translate a few to my native garden but I don't know much about this plant other than it is interesting looking. Would this be a bad idea?

ANSWER:

Silybum marianum (Milk thistle) is a native of Southern Europe, the Mediterranean area and North Africa.  As an introduced species to North America it is considered invasive or, at the very least, a noxious weed in many areas.  It is on the Arkansas Noxious Weeds List, the Oregon Noxious Weeds List and the Washington Noxious Weeds List. Here is a link from King County, Washington with information about its bad qualities.   On the other hand, it is also praised for its herbal medicinal properties, but see also the Mayo Clinic reference.  All in all, I would say it would be a pretty bad idea to grow milk thistle.  First of all, it's not native to Texas nor even to North America.  Second of all, it has the potential to be a problem plant if it escapes your flower beds and the seeds can be distributed by the wind.  Why not get seeds of one or more of the Texas thistle species [Cirsium texanum (Texas thistle) or Cirsium horridulum (Yellow thistle)] to grow?

 

From the Image Gallery


Texas thistle
Cirsium texanum

Yellow thistle
Cirsium horridulum

More Non-Natives Questions

Non-native Dietes bicolor leaves brown after freeze in Austin
January 31, 2010 - I live in Austin, and my butterfly iris (Dietes bicolor) that I've had for the last 6 years are all turning brown after the most recent freeze. Should I cut them back, with the thought being they wo...
view the full question and answer

Non-branching mimosa tree
June 26, 2008 - I have a Mimosa Tree, just about 2 years old, grown from seed. The problem with it is that it has not branched out, it looks like one long branch growing out of the ground, about 5 feet if stood strai...
view the full question and answer

Something eating cannas in Austin
July 14, 2012 - What is eating my cannas?
view the full question and answer

Consumption of carbon dioxide from South Korea
December 07, 2011 - I am curious about what flowers consume CO2 for growing (especially 1-year life flower). Thanks.
view the full question and answer

Leaf color in non-native sago palms
January 24, 2009 - I have two sego palms planted in my front yard. Lots of sun. The fronds have turned a lime green color instead of the dark green color. Please help...(alkaline soil)
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center