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
Not Yet Rated

Monday - October 13, 2008

From: Clarendon Hills, IL
Region: Midwest
Topic: Diseases and Disorders, Herbs/Forbs
Title: Mildew in Phlox paniculata
Answered by: Barbara Medford

QUESTION:

I planted garden phlox (phlox paniculata) in my front landscaping and it is suffering from mildew. It is wet on that side due to a down spout and it may benefit from being split. Does anyone know of a treatment to eliminate the mold? They really do not flower well.

ANSWER:

Your native Phlox paniculata (fall phlox) is probably not in any danger from the mildew, although it does make the plants somewhat unattractive. Mildew is common in the Fall, because of cool nights and still-warm days. Too much water in a flower bed, such as from a downspout, can cause other problems in plants, like root rot. You might want to consider finding a way to channel the outflow from your downspout away from the flower bed. Since your phlox is a perennial, you might also consider dividing it and moving it to another area. The best preventions of mildew are good air circulation and sunshine. Since it isn't always possible to provide those, read this article from About.com Organic Gardening on   Preventing and Controlling Powdery Mildew. One tip we picked up from this and other sources, which surprised us, is that one of the best treatments for powdery mildew is a good spray of water on the affected plants. It should be done early in the day, so that the water will have plenty of time to dry before sundown, but it does seem to work. You could go on to try the baking soda spray solution mentioned in the article, although we have heard mixed reports on the efficacy of that method. There are fungicides available, but that is likely overkill for this problem. Rake up the fallen leaves and blooms, and keep the area clean, so mildew can't winter over.


Phlox paniculata

 

 

 

More Diseases and Disorders Questions

Yellowing of Leyland Cypress in Roswell, GA
April 27, 2010 - We paid for 12 foot naylor blue leyland's to be planted behind our home. This is their first season in the ground here - they came from a tree farm - there is yellowing on some of the branches and w...
view the full question and answer

What is wrong with my Weeping Willow?
June 15, 2009 - I have a weeping willow tree for about 7 years. It's about 50 feet high and the bark is separating and it starting to drip and collect on trunk bottom a suds type substance. Looks like soap suds. T...
view the full question and answer

Changing bloom color from Tulsa OK
June 27, 2011 - How do you change the bloom color?
view the full question and answer

Leaves browning on non-native willow from in Cumbla PA
July 10, 2011 - We recently planted a willow tree. A lot of the leaves turned yellow and some turned brown, but it is also getting some new buds. my question is, should I take the dead leaves off or leave them there...
view the full question and answer

Red oaks that didn't drop leaves in Austin
April 04, 2012 - I have a number of Red Oaks on land that did not drop leaves this past fall. Now these same trees seem to be dead? It seems there's some type of mold/fungus on the trees. Some trees have small patche...
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center