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?


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
1 rating

Thursday - April 05, 2012

From: Phoenix, AZ
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Texas wild olive tree
Answered by: Ray Mathews


I live in the Phoenix area. My Texas wild olive (Cordia boissieri) is about 5 years old, about 12 feet tall and has beautiful blossoms all year long. However, this past year (through all seasons) some of its leaves developed yellow/brown spots and other leaves are completely brown and falling off. I am not able to find much information on the diseases of this plant. Might this be a lack of N2? a mold? overwatering? ???? Any guidance you might be able to provide would be appreciated. Thank you.


The wild olive tree Cordia boissieri (Mexican olive) is an evergreen native only to Texas in the U.S.,  but also to several states in northern and southern Mexico, including Coahuila, Nuevo Leon, San Luis Potosi, Tamaulipas, and Veracruz, per the following Agricultural Research Service, Germplasm Resources Information Network link. This rare small tree is reportedly ideal as an ornamental for confined areas. It is drought tolerant and insect and disease pests are generally of no concern. Birds and other wildlife feed on the fruit. It blooms in late May through early June.

However, since Cordia boissieri isn’t native in Arizona , it may be the wrong plant for Arizona. The symptoms you are observing may be due to mold or overwatering. We don't believe that nitrogen deficiency is the problem.

Bill Britt’s garden website offers the possibility of frost as an immediate cause, but the earlier browning does not follow the description for these symptoms?

We believe that you need someone who can look at the plant, and make an informed assessment. For that we suggest you contact the folks at the Maricopa County Office of Arizona Cooperative Extension for some help closer to home.





From the Image Gallery

Mexican olive
Cordia boissieri

More Trees Questions

What grows in Tampa FL
July 01, 2013 - Please let me know what grows in the backyard in Tampa, FL to provide screening and privacy?
view the full question and answer

Need substitute plants for Red Tip Photinia in San Antonio.
April 14, 2009 - Looking to replace Red Tips with major leaf spot infections. Need about third replaced. What suggestions would you have to replace these privacy hedge row type plants? Need a plant that will grow at...
view the full question and answer

Recommend a plant similar to Corkscrew Willow for Austin, TX.
June 16, 2015 - Do corkscrew willows do well in Austin, TX? If not, can you recommend a willow like tree to plant along the banks of a creek?
view the full question and answer

Looking for yellow bottlebrush (Callistemon sp.) and native substitutes
February 14, 2008 - I have been looking for years for a yellow bottle bush. It is identical to the red but is yellow. there are several varieties, but the one i want is just like the red one in appearance. I live in Flor...
view the full question and answer

Is Viburnum rufidulum monoecious or dioecious?
July 28, 2014 - Is Viburnum rufidulum monoecious or dioecious? Your database does not address this for most plants.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center