En Español

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

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
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

Defenses against imported red leaf beetles on lilies
August 06, 2007 - I've recently discovered small red beetles of some kind on my lilies, which they are happily devouring. I've been picking them off with my fingers and squashing them, but I'd like a better alterna...
view the full question and answer

Leaf Galls on Live Oak
March 20, 2012 - Hi - I have a live oak tree that always seems to have thinner foliage than our other two. Upon closer examination today I found small brown balls all over the mature leaves. The balls look and feel ve...
view the full question and answer

Groundcover for vineyard from Round Rock, TX
February 04, 2013 - I will be planting a vineyard in the Hill Country next spring. I am looking to maintain low-growing understory plants across the entire vineyard to maintain soil health, choosing plants that the leaf...
view the full question and answer

Problem with leaves of Texas Ash in Austin
May 21, 2012 - We purchased a 3' to 4' Texas Ash in March 2012. The past few days I noticed new leaves at the top are curled under, have a milky substance on them, and more than a few ladybugs on them. What is thi...
view the full question and answer

Failure to thrive of Lantanas
August 06, 2008 - Here at work we have 4 beautiful yellow Santanas(should I say had), the leaves have started to turn brown and no longer blooming. Appears to have a fungus or disease. Please help!
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center