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
3 ratings

Sunday - April 27, 2008

From: Leander, TX
Region: Southwest
Topic: Pests, Herbs/Forbs
Title: Problem with Eupatorium greggii
Answered by: Barbara Medford

QUESTION:

At the Garden's fall plant sale in 2006, I bought some Eupatorium greggii. It did very well last year. Recently, the entire plant looks like it is just wilting from the top down, as if it has some sort of disease. Moisture is not the problem. The Conoclinium greggii I have elsewhere does not seem to be affected. Do you have any idea if this plant is prone to a virus? Any other ideas?

ANSWER:

Eupatorium greggii is now considered a synonym for Conoclinium greggii (palmleaf thoroughwort), which explains why we couldn't find Eupatorium greggii in the Native Plant Database. Beyond that, however, we are still very puzzled as to what could be causing your plant to decline. Have you checked for red spider mites or whiteflies? Try tapping an affected leaf over a sheet of white paper-if you get little red spots, that's red spider mites. If you see what looks like flying dandruff, that is whiteflies. Honeydew excreted by whiteflies glaze both upper and lower leaf surfaces, causing the development of black sooty mold fungus. Just about every reference we checked referred to Conoclinium greggii (palmleaf thoroughwort) as almost pest and disease free, but you may have gotten caught in the "almost." The only other possibility we could think of is that this plant needs afternoon shade, and if it is in full sun all day, it will need additional water. These are very sturdy plants, and spread by rhizomes, which sometimes makes them almost a nuisance, but they are wonderful for butterflies. We would suggest that, if you feel the insects mentioned are the culprits, that you first trim out all the affected foliage, and dispose of it where the insects living on it will not be transported to other plants. Then try a weak solution of Safer insecticidal soap, sprayed on it two or three times in a week, because of the various stages of development the whitefly goes through. The main point is to prevent the spread of these insects to other plants in your garden, so you'll need to keep a watch out for that.

 

More Pests Questions

Holes in leaves of wax myrtle from Austin
April 30, 2011 - I just purchased 4 of the 5 gallon Wax Myrtles at the last spring plant sale and after planting them, they are getting eaten by bugs leaving holes in the leaves. I can't find any of the bugs doing th...
view the full question and answer

Cotton plant for yard in Plano
July 27, 2008 - I wish to plant a specimen cotton plant in my yard - will it grow in Plano, Texas, do you have any tips for maintaining them, and will they survive freezing temperatures?
view the full question and answer

Removing bermudagrass from buffalograss in Smithville TX
May 01, 2013 - I have a lawn created two years ago with buffalo grass sod in Smithville, TX. Recently several areas of bermudagrass have started to flourish in the buffalo grass lawn. Can you recommend a herbicide...
view the full question and answer

Dry browning leaves on Monterrey Oak from San Antonio
August 08, 2013 - I have a Monterey Oak that was planted four years ago and was doing great until the last two weeks. It has turned brown and the ends of the branches are very dry and brittle. The root flare was cov...
view the full question and answer

Swarming insects on non-native willow in Washington PA
September 25, 2011 - I have had a very large, beautiful pillow willow bush/tree growing next to our garage for about 8 years. Last year at the end of August, it began to attract white-faced hornets and yellow jackets by t...
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