En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Disease on non-native French hollyhocks

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

Wednesday - April 16, 2008

From: Georgetown, TX
Region: Southwest
Topic: Non-Natives
Title: Disease on non-native French hollyhocks
Answered by:

QUESTION:

I live in Georgetown, Texas. I have some French hollyhocks that have some kind of disease on the leaves - I would like to know what to spray them with to get rid of it. It looks like brown blemishes all over the leaf and the blemishes are small and round. It really looks gross. One of our local nurseries said it might be a bacteria of some kind but they weren't that helpful. I pulled off the infected leaves and the new growth eventually got the same thing. Please help! The plants have been hearty and a dark green until about a month ago.

ANSWER:

The French hollyhock is a lovely old garden flower; in fact, legend has it that Thomas Jefferson grew it at Monticello. That does not mean, however, that it is native to North America, indeed, it is native to Europe, north to Scandinavia and east to Russia and the Caucasus. The Lady Bird Johnson Wildflower Center is dedicated to the care and propagation of plants native to North America, so this is a little out of our field of expertise. However, we are always glad to help out, if we can, with problems gardeners are having with their plants. We hunted around for information on Malva sylvestris, French hollyhock, and mostly found that it had no serious insect or disease problems, although Japanes beetles can be a problem, where present. We did find one reference with said that the Malva sylvestris can be prone to rust fungus. Not having a clue what that was, we searched some more and found this website on rust fungus that is probably going to tell you more than you ever wanted to know, but there are a lot of pictures you can compare to the blemishes on your flowers. If you feel that is the problem, ask your nursery to recommend a good fungicide, and apply it exactly as instructed. Good luck!

 

More Non-Natives Questions

Yellowing leaves on non-native jasmine from Austin
June 25, 2012 - Hi, I have a mature jasmine plant in the ground in a very sunny courtyard which gets watered daily. The lower leaves are turning yellow and am wondering if this is too much water for it. The top lea...
view the full question and answer

Vine Choices Scarce in Beaverton Oregon
June 08, 2012 - Hi, I am looking for a hearty vine that we could use to cling to and cover a cement wall that is about 8 feet tall and 30 feet long. It is on the south side of our house but never gets direct sunli...
view the full question and answer

Survival of non-native Cape Plumbago in Delaware
October 18, 2008 - I have a cape plumbago shrub growing in a large pot outdoors - but we are in Delaware - where it won't apparently survive the winter. How can I keep my plumbago safe over the winter?
view the full question and answer

Black Sooty Mold on Bay Tree
February 25, 2013 - I have a large bay tree and all the leaves are covered with a black mold-like substance on the top part of the leaf. Under each leaf are some black/brown spots. I have washed the leaves with soap and ...
view the full question and answer

Ants in vegetable garden in Muskogee OK
May 25, 2011 - I have ants in my vegetable garden this spring - I think because of all the rain. I think they are the culprits that ruined my spinach and swiss chard. They have left all the lettuces alone..but you...
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