Native Plants
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
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.
rate this answer
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 redbud. Cercis 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
More Trees Questions
Soapberry tree problems in North Richland Hills, TX
September 01, 2010 - We have a small grove of soapberry trees. The city recently reconstructed the street and added a side walk which now sets as close at 1 foot from the nearest tree. Everything seemed fine until they ...
view the full question and answer
Trimming of Escarpment Oak from Austin
May 18, 2014 - We have a 2-year-old quercus fusiformis in our front yard and have been advised by some people that we need to remove the bottom branches and trim the ends of the branches that are hanging far down. ...
view the full question and answer
Native plants for Pflugerville, TX in blackland soil
March 21, 2008 - Mr. S-P,
I'm perusing the plant sale list for a couple of tall shrubs to plant on the sunny southwest side of my house, in Blackland soil. It is generally dry there because of the sun, but can ge...
view the full question and answer
Should wax myrtles (Morella cerifera) be pruned?
April 26, 2007 - We planted Wax Myrtles in our backyard as a wall for privacy from the lot behind ours. Should we prune or cut back the tops periodically to get more fully developed bushes or let them grow naturally?
view the full question and answer
What's attacking my Nellie Stevens Holly plants in Iredell, TX?
June 27, 2011 - I just bought 10 Nellie R. Stevens holly bushes and planted them as a screen. The leaves on some of the plants are at least half white - not yellow but white. Apparently they were like that when I b...
view the full question and answer
| Support the Wildflower Center by Donating Online or Becoming a Member today. |