Contact Us Host an Event 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

Friday - July 11, 2008

From: Portland, OR
Region: Northwest
Topic: Diseases and Disorders, Shrubs
Title: Leaf burn on hydrangeas
Answered by: Barbara Medford

QUESTION:

What causes my leaves to burn on my healthy hydrangeas?

ANSWER:

Our first thought would be too much sunshine, as the hydrangea thrives best as an understory plant with dappled shade. However, in Portland that doesn't seem like a big danger. Hydrangeas are susceptible to sunscald, chlorosis in alkaline soils, and winter dieback. Many weak, brittle canes are easily broken in wind and ice. Forms colonies from a shallow root system. Canes can be cut to the ground every two or three years to keep the shrub smaller, but if the canes are allowed to grow, the naturally peeling bark is attractive. Pest free. Prune immediately after flowering. There are three hydrangeas native to North America, but they tend to be more in the southern United States and none are native to Oregon. If it appears that the plant is getting too much sun, give it extra water, making sure it is not standing on the roots, and try to arrange a little more shelter for the plants next summer.

If that doesn't appear to be the problem, look at this Alabama Cooperative Extension article on Diseases of Hydrangeas. There are good illustrations of each of the symptoms of the various diseases, as well as suggested treatments. And you can go to this Oregon State University Extension page and try to find out if other similar plants in your area are being similarly affected.

 

More Diseases and Disorders Questions

Teucrium resistant to Verticillium Wilt?
April 20, 2015 - Is Teucrium frutescans, or Bush Germander resistant to Verticillium Wilt? I cannot find it on a list anywhere.
view the full question and answer

Is Sabal minor juglone tolerant?
October 13, 2014 - Is Sabal minor or any other small and shade tolerant palm juglone tolerant? Id like to plant one in an area near a pecan tree but I am not sure if they will play well together.
view the full question and answer

Transplant rootbound tree now from Kerrville TX
June 10, 2012 - I purchased a Blanco Crabapple tree. Should I plant it now or wait until Fall? (It is currently rootbound.) Second question: Our Mountain Laurel has a dead trunk and one trunk has already died. I c...
view the full question and answer

Huisache tree is not thriving in Kerr County, TX.
May 18, 2011 - Our landscaper planted a Huisache tree in our back yard (Kerr County). It was planted about 3 years ago. It has grown considerably (about 15 feet tall)but it has never flowered and is always late in...
view the full question and answer

Stressed live oaks from Lakeway TX
August 19, 2013 - I have some Live Oaks who appear to be stressed (Ball Moss is becoming very prevalent on some of them) during the drought in Central TX. How often and how long should I water them? Thank you very much...
view the full question and answer

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