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?


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
2 ratings

Monday - July 05, 2010

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders, Herbs/Forbs
Title: Cottony infestation on Turk's Cap in Austin
Answered by: Barbara Medford


The Turks Cap in my front planter is well-established and, overall, happy and blooming. However, some of the top leaves, those in the most shaded area, have what looks like a thin, loose layer of cotton. These leaves are also a bit puckered. Any suggestions as to what this is (a mold, perhaps?) and what, if anything, needs to be done to remedy the situation? The planter also contains a couple of medium size(>two story) live oaks, wedelia, Tx. mountain laurel, purple oxalis, cedar sage, rock daisies, flame acanthus, dwarf ruellia, winecup, and evening primrose. Your help is greatly appreciated


Generally, the Malvaviscus arboreus var. drummondii (wax mallow) is a pretty tough, well-adapted plant for our area, and not much bothered by pests and diseases. There are three insect pests that can disturb it, creating various symptoms of the presence of the pest, one of which might be the "cotton" you are seeing on the leaves. Go to the websites indicated to see the symptoms, matching them up with your observations, and find a treatment that seems reasonable to you in the situation. Given the area where you are seeing this cotton, we would suggest that you trim back the area of the Turk's Cap that seems most affected. Since you have already observed that it is worse in the most-shaded area, and since you can prune Turk's Cap nearly all year long and not damage it, we would certainly suggest that you trim that out of the shady area, and dispose of it so whatever bug is causing the problem will not get an opportunity to spread somewhere else. 

Aphids: these will definitely cause leaf curl, and the honeydew they excrete begins as a whitish area, although it can develop a black fungus that will change the color and is really ugly. University of California Integrated Pest Management Aphids

Spider mites: this is probably the best suspect in your case, as the spider mite is a member of the Arachnid (spider) family and has web-spinning abilities. Again, from the UC IPM program Spider Mites

Mealy bugs: these individual bugs can also have a cottony appearance, and you can find some easy control methods in this eHow site How to Control Mealybugs.

From our Native Plant Image Gallery:

Malvaviscus arboreus var. drummondii

Malvaviscus arboreus var. drummondii

Malvaviscus arboreus var. drummondii

Malvaviscus arboreus var. drummondii



More Diseases and Disorders Questions

Bloom color change in Choctaw Crape Myrtle
July 30, 2007 - In 2006 my wife bought a Choctaw Crape Myrtle from a local nursery. It had a tag from Greenleaf Nursery and had several blooms in the "correct" pink color. The plant was 5-6 ft tall. It has grown...
view the full question and answer

Fronds turning brown on yucca in Leander, TX
April 13, 2009 - Dear Mr. Smarty Plants, I live Northwest of Austin in Leander and have grown a spanish dagger yucca for several years. It is 8 feet tall and each spring it puts up a showy spike of blooms. The old fr...
view the full question and answer

Dying foliage on non-native Otto Luyken Laurel from Georgetown KY
April 09, 2014 - I have 5 luken laurel scrubs planted around foundation. They have done very well until this last winter..the foilage is now brown and crispy. Will they come back? Do I need to prune back the damage...
view the full question and answer

Sudden death of one side of Mountain Laurel from Canyon Lake TX
July 22, 2013 - Hello! We live in Canyon Lake TX and have a Mountain Laurel that is in distress. It is planted in an irrigated flower bed and has been happily growing for 5 years. It is about 5' tall and has sever...
view the full question and answer

Weeping Willow Problem in Texas
September 04, 2014 - Our weeping willow's leaves are turning yellow and falling off. We are also seeing some brown, gnarly looking pods on some of the stems can you tell us what's happening?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center