Host an Event Volunteer Join Tickets

Support the plant database you love!

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

Wednesday - August 07, 2013

From: Newport, RI
Region: Northeast
Topic: Non-Natives, Diseases and Disorders, Pests, Shrubs
Title: Possible maple scale on non-native mophead hydrangeas from Newport RI
Answered by: Barbara Medford

QUESTION:

I have a mophead hydrangea that has small white cottony tufts under the leaves and on the stems. I believe this is maple scale. Is there a home remedy I can use to rid this disease?

ANSWER:

There are 4 members of the  Hydrangaceae family in our Native Plant Database, indicating that they are native to North America. They are: Hydrangea arborescens (Wild hydrangea), Hydrangea cinerea (Ashy hydrangea), Hydrangea quercifolia (Oakleaf hydrangea) and Hydrangea radiata (Silverleaf hydrangea). Hydrangea macrophylla, (Mophead hydrangea) is native to China and Japan and therefore out of our range of expertise. However, we know that many are grown in the United States and some Internet research turned up some information that will perhaps lead you to a solution to your problem. In response to your question, no, we do not know of any "home remedy" for your problem, and in fact, don't know for sure what your problem actually is. Because local gardeners are more apt to know about locally grown plants, we suggest you contact the University of Rhode Island Cooperative Extension Office to learn if others are experiencing the same difficulties. Then, follow these links to other university and national sites on specifics of the problem:

University of Rhode Island Master Gardeners

Alabama University Cooperative Extension System Diseases of Hydrangea.

United States National Arboretum Pests and Diseases of Hydrangea macrophylla

Washinton State University Extension Scale Insects on Ornamentals

 

From the Image Gallery


Wild hydrangea
Hydrangea arborescens

Oakleaf hydrangea
Hydrangea quercifolia

More Shrubs Questions

Transplanting Evergreen Sumac
December 09, 2015 - I would like to transplant evergreen sumac from my back to the front yard. They are about 6-8 foot tall. I live in El Paso, TX and it gets plenty of sunlight. I am wondering 1) Is November in El Paso,...
view the full question and answer

Making cuttings from purple sage in Austin, TX.
May 15, 2012 - I would like to plant additional purple sage for landscaping. May I do this with cuttings from an existing adult plant? If so, how and when would be the best method? I live in Lago Vista, TX
view the full question and answer

Preventing weeds in kinnikinnick in Richland WA
May 29, 2011 - We planted our kinnickinick last Nov. and we live in Richland, WA, where it gets hot in the summer. We planted almost 500 of them on a hillside. Weeding is taking over our lives, to say the least. ...
view the full question and answer

Yaupon sprouts from Bennettsville SC
May 29, 2013 - I have Yaupons in a flower bed and they have too many shoots to pull up, can I spray them with roundup and not kill the bush and what strength should I use?
view the full question and answer

Identification of shrub in South Carolina
December 12, 2011 - First, I'm in Iraq but trying to write a book and have a question on a plant that grows in South Carolina. All I can do is describe it. The bush is normally green but turns red, has large leaves, kin...
view the full question and answer

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