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

Friday - June 15, 2007

From: Round Rock, TX
Region: Southwest
Topic: Non-Natives
Title: Decline in non-native crape myrtles
Answered by: Joe Marcus

QUESTION:

I live in Round Rock and the ground is rocky about one foot beneath the surface. I have about 14 crape myrtles that have been doing very well for about 6 years now. Last year the leaves on 1 started turning red and then yellow and it didn't grow or flower no matter what I did. This year, 2 more besides the 1 have also started turning yellow. I sprayed for mold and also used fertilizer with iron but nothing helps. What could be going on with them?

ANSWER:

The focus of study and the limit of expertise of the Lady Bird Johnson Wildflower Center is limited to plants native to North America. Crape myrtles (Lagerstroemia spp.) are native to other parts of the world. However, we can give you some general advice. Crape myrtles are normally not very susceptible to disease or insect problems. High nitrogen fertilization can cause problems similar to those you describe. At any rate, it is usually not a good idea to feed declining plants. We would suspect a problem associated with nutrition or a root-related problem.
 

More Non-Natives Questions

Growth rate for eucalyptus in Florida
September 21, 2006 - How fast does eucalyptus grow in Florida?
view the full question and answer

Problems with non-native mimosa
August 29, 2008 - We have 2 large mimosa trees in front of our house that are close to 50 years old. They have not been cared for over the past 8 years (we did not live here). This year, I trimmed them, removed dead ...
view the full question and answer

Non-native blue potato bush in El Dorado Hills CA
June 12, 2010 - I have two blue potato bush topiary planted in my front porch in a very big planter. It's getting a full afternoon sun. I am wondering why they are losing their leaves??? Am I overwatering them??? Al...
view the full question and answer

Rose varieties for Alabama
October 26, 2009 - What climate and soil types will Rosa Rogosa, a plant that grows in MA, require?
view the full question and answer

Non-native red-tip photinias dying in San Antonio
August 20, 2009 - A 17 year old Red tip Photinia in a hedge shows signs of dying. The main stalks are quite large and offshoots from two of the stalks have brittle, drooping leaves. The center of the plant looks norm...
view the full question and answer

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