Native Plants
![](../_images/smarty_plants.gif)
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
![](../_images/mr_smarty_plants_logo_web_200w.jpg)
rate this answer
![](../_images/star_00.gif)
Monday - September 22, 2014
From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Why are my Rock Roses dying?
Answered by: Joe Marcus
QUESTION:
I planted several rock roses last fall. This spring they have grown wonderfully, but all of a sudden, one shriveled and died. I took it out and replaced it. Now, another is starting to shrivel. It starts in one branch, then spreads across the plant. The plants on either side are thriving. What is happening?ANSWER:
Several unrelated plant species are known in various places as Rock Rose. Because of your location in Austin, TX, we're going to assume that you're are referring to Pavonia lasiopetala.
Except in very rare cases, it is not possible to positively diagnose most plant diseases and disorders sight unseen. We recommend contacting your county's AgriLife Extension Service office for details on submitting a plant sample for disease testing. However, if the cause of your plants' problems are not disease-related, the test will only be able to rule out a pathogenic cause.
Our first thought, though, is that the most likely malady besetting your Rock Roses is Cotton Root Rot. Cotton Root Rot -- caused by the fungus, Phymatotrichum omnivorum -- is probably most serious disease of ornamental plants in Texas.
Plant species susceptible to this disease should not be planted in soil that previously held Cotton Root Rot-infected plants as the pathogen remains in the soil and can infect new plants long after dead plants have been removed.
From the Image Gallery
More Diseases and Disorders Questions
Need help with yucca palm in New York City, NY.
November 10, 2011 - I have had my yucca palm plant for almost 10 years. The bark has started to peel off although leaves seem fine. The second smaller separate yucca plant has half its bark and trunk gone. I can't see a...
view the full question and answer
Palm trees turning orange in Miami
May 24, 2010 - Why are my palm trees turning orange?
view the full question and answer
Loss of bloom on Fremontodendron californicum in California
June 11, 2009 - The flowers on my Flannel Bush all died at once I have noticed a sappy substance at the base of the trunk. There are still some flowers on bush but most are dead. It has been blooming since Feb. Is ...
view the full question and answer
Possible disease on Eastern Redbud
October 06, 2007 - Our Eastern Redbud appears to be suffering from our recent drought. The leaves are turning brown in July/August on a few branches. A few black spots appear on the leaves before they turn brown. Ot...
view the full question and answer
Black fungus on cholla cactus from Austin
March 25, 2012 - How to get rid of black fungus on cholla cactus? Cut it off? And treat with what?
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |