Rent Shop 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

Sunday - May 02, 2010

From: San Antonio, TX
Region: Southwest
Topic: Planting, Pruning, Shrubs
Title: Cold damage to Texas wild olive tree in San Antonio
Answered by: Barbara Medford

QUESTION:

I have a Texas Olive tree that was unprotected from the 2010 cold winter here in San Antonio, TX. It is the end of April and there is no sign of growth on any of the branches. If the tree is still alive, when can I expect to see signs of growth? Should I assume the tree is dead and replace or should I continue to wait and see?

ANSWER:

From a previous Mr. Smarty Plants answer:

 

"We have been receiving many questions regarding what to do after the sudden hard freeze that occurred recently in Central Texas. One thing that applies in every case is, don't fertilize. Plants should be fertilized in the Spring, when you want to encourage new shoots to appear. The last thing you want to do is encourage new shoots now that will put more stress on already-stressed roots.

You may already know what happened; actively growing plants still have water in their upper structure, particularly the leaves. A sudden hard freeze causes that water to expand, bursting cell walls in the leaves, and they quickly turn dark and look pathetic. What made this freeze worse was that it was earlier than we ordinarily expect these conditions in this part of Texas, very sudden, temperatures went down very far, and remained below freezing for several hours. A gradual decrease in temperature over a period of time increases the ability of plants or plant parts to withstand cold temperatures. A sudden decrease in temperature in late fall or early winter usually results in more damage than the same low temperature in January or February.

The information that you found in our database is exactly what we know about the hardiness of the Cordia boissieri (anacahuita).  Was your plant protected from those hard, cold winds we had during our cold snap? If so, that might give you a better prognosis. The first thing to do is determine how much of the tree is still alive. Obviously, the leaves, probably black, are going to drop off. On the trunk and branches, use the thumbnail test. Scrape away a very fine, very small layer of the bark, beginning with upper branches and working down toward the base. If there is still some green beneath that scraping, that part of the plant is still alive. If it is black or even slimy beneath the outer bark, that portion of the plant should probably be marked for pruning. The good news is that the bark and woody portions of the tree have stronger cell walls, and are not so apt to burst in freezing. 

From Texas A&M AgriLIFE Extension this article Follow Proper Pruning Techniques will give you some good information on what and when to prune. In any case, we would not disturb it except to remove dead areas, and wait to see if it starts to come back in the Spring. Hopefully, the roots were well enough protected by the soil to keep them from freezing, too.

This is an illustration of why the Lady Bird Johnson Wildflower Center recommends the use of plants native not only to North America but to the area in which the plant is being grown. You knew you were gambling to plant the Mexican olive this far north; we hope that you will ultimately win the gamble and retain a live tree."

From our Native Plant Image Gallery:


Cordia boissieri

Cordia boissieri

Cordia boissieri

 

 

 

 

 

 

More Planting Questions

Scorched leaves on Red Maple from Lufkin TX
April 30, 2012 - I have a Red Maple that we planted in Lufkin, TX about a month ago and fertilized about 2 weeks ago. We water the tree often. The leaves have become scorched looking on the outside of about 1/3 of t...
view the full question and answer

Transplant shock in non-native crape myrtle from Wesley Chapel, FL
June 12, 2012 - I just bought a 12 ft. crape myrtle and planted it, giving it plenty of water I think. After 3 days the leaves are wilting and flowers are falling off.
view the full question and answer

Problem with Live Oaks in Mesa AZ
March 26, 2013 - I have two Evergreen Live Oaks in central Arizona. One is flourishing and getting new spring leaves from top to bottom. Its trunk is rough, has large grooves, and the spots where I've pruned look li...
view the full question and answer

Replanting a Desert Willow
February 07, 2016 - My desert willow was damaged badly in a winter storm and had to be taken down. Do I need to remove the old root system below grade when I plant a new desert willow?
view the full question and answer

Grouping plants according to water needs
February 05, 2010 - Explain how appropriate design/grouping of plants of the same water needs would make irrigation scheduling easier?
view the full question and answer

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