Rent Shop Volunteer Join

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
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

Newly planted nuttall oaks from Houston TX
November 16, 2012 - I recently purchased two Nuttall Oak Trees in Houston Texas (October). They are both 15' or taller. I planted them within 24 hours of being delivered, watered them in, staked them, and within 3-4 d...
view the full question and answer

Problems with mountain laurel from Sunrise Beach TX
August 29, 2012 - In Llano Co., TX near lake LBJ, crushed granite type soil - my 4 - 5 year old TX Mtn. Laurels (2), about the size of large wheel barrows, are turning very pale, dropping leaves and on 1 the seed pods ...
view the full question and answer

Green worms on salvias
October 12, 2008 - I recently bought a "salvia blue chiquita." Some leaves were yellowing, but full of flowers and still attractive. Have had it on my deck for less than a week and have found 2 tiny greenish "worms...
view the full question and answer

Death of mature Eve's necklace in Fredericksburg, TX
July 12, 2010 - A friend mentioned his mature Eve's necklace had died this year. The next day I walked past my own mature Eve's necklace(about 5 years old)and it was dead! What could have happened? Thanks.
view the full question and answer

Problems with Savannah Holly plants in Friendswood, TX.
June 17, 2009 - I have planted 4 savannah hollies in front of my house, two on the left of the door and two on the right. If you are standing in front of my house and looking at the door, the sun rises at the back l...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.