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

Friday - July 13, 2012

From: Denton, TX
Region: Southwest
Topic: Diseases and Disorders, Watering, Trees
Title: Redbud leaves turning yellow in mid-summer
Answered by: Guy Thompson

QUESTION:

The leaves on our redbud trees are turning yellow. The yellow leaves are pale with no other spots and no dark veins. I don't know for sure which variety of redbud they are or how old they are (more than 10 years old). The heat and drought of 2011 hit us pretty hard. Is this a result of last year's drought, or is there something else going on? What can we do to save them? Thank you!

ANSWER:

Redbuds and many other trees normally drop some leaves early when drought-stressed.  This is an adaptation to reduce the need to take up moisture from the dry soil.  Don't worry too much if the branches are still alive (scrape off the bark on a defoliated twig to see if it has green and moist tissue) and if 50 % of the leaves remain green.  New leaves will appear next spring.

If a great number of leaves are turning yellow, the trees may still be drought-stressed.  Drought stress can show up even a year or two after a drought because part of the root system has not yet recovered.  If that is the case, you should make sure that the soil around the trees remains moist.  Deep watering throughout the root zone (out to the drip line) once a week will assure that the trees are not short of water.  Mulching the area under the trees will help conserve soil moisture.

Plant nurseries around the country sell several varieties of redbudCercis canadensis var. texensis (Texas redbud) is more drought-resistant than Cercis canadensis (Eastern redbud) and less drought-resistant than Cercis canadensis var. mexicana (Mexican redbud).  The seed pods of Texas redbud tend to be reddish in color while the Eastern redbud seed pods remain green.  That may help you identify yours.

Drought stress would make the trees more susceptible to disease.  It is possible that you trees are not drought-stressed but suffering from verticillium wilt.  Here is a web site on this subject. 

Good luck in keeping these attractive trees alive!

 

From the Image Gallery


Texas redbud
Cercis canadensis var. texensis

Eastern redbud
Cercis canadensis

Mexican redbud
Cercis canadensis var. mexicana

More Trees Questions

Problems with non-native Chinaberry tree from Tucson AZ
September 05, 2013 - I have a 30+ year old Chinaberry tree and this year the branches are much sparser with leaves and there are a lot of small dead branches. Should I fertilize and what should I use? Thank you
view the full question and answer

Problems with Eastern hemlock in Greenville SC
July 02, 2009 - Dear Mr. Smarty Plants, I have a beautiful, young, 5 and a half foot tall Eastern Hemlock. I purchased and planted it two years ago in the fall. It has been doing very well all this spring. And ne...
view the full question and answer

Shallow topsoil on rocky substrate in SW Oregon
April 28, 2009 - I want to plants some shrubs and trees. Trouble is I can't plant very deep. I have mostly rock within 5 inches. Please help.
view the full question and answer

Native trees of Hornsby Bend in Austin, TX
April 10, 2013 - We are looking for a list of the trees occurring along and in the vicinity of the Colorado River at Hornsby Bend circa 1820.
view the full question and answer

Native plants for city lot in Longview, TX
March 19, 2008 - Just bought a city lot in Longview, TX and want to put in some plants at the periphery even before the house is built. Can you recommend any that would be from your list of East TX plants that are pa...
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