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

Sunday - May 02, 2010

From: Austin, TX
Region: Southwest
Topic: Pruning, Watering, Trees
Title: Failure to thrive of Texas Mountain Laurel in Austin
Answered by: Barbara Medford

QUESTION:

I have an adult (over 25 years?, 20 feet tall?) Mountain Laurel next to my house in Austin. The winter of 2009/10 it lost most of its leaves. It did bloom and leaf out this Spring--not vigorous especially, not on the top. Is it completing its life span indicating I should take it down and replace it? Or, should I give it another year or two to see if it comes back? Possibly resulting from a combination of the drought and extreme 2009 winter weather. I don't see similar specimens in my neighborhood in similar condition. Thank you for your advice.

ANSWER:

Sophora secundiflora (Texas mountain-laurel) is native to the Austin area, so we can't blame the problems on it being out of its territory. You are absoutely correct that even native plants, well adapted to our uncertain climate, have suffered this past couple of years. However, everything we looked at researching this plant says that its mature height is 10 to 15 ft.,  but none of the material said how old it was expected to get. Generally speaking, the slower a plant grows, and this one grows very slowly, the longer it will live. So, it would seem your tree is mature, but not necessarily senile, ready to die. The only possible change we can think of that might cause some decline in a tree that well developed is if there has been a change in the drainage. This is a plant accustomed to growing in desert areas and limestone, which is why it is so slow-growing. It needs good watering, especially in Spring and Summer, but also good drainage. If it has not been receiving supplemental watering during the very dry last two years, and now there has been rain, it may have feet standing in water beneath the surface of the soil, especially if you have clay soil. 

We certainly would not recommend taking down a mature and apparently healthy tree just yet. Don't fertilize it.  Often, that is a knee-jerk reaction when a plant does poorly, to fertilize. A plant under stress should never be fertilized, and with this tree, with the blooming already past for this season, you sure don't want to send a message to inspire new growth. Furthermore, this is a plant that really should never be fertilized, it is so well-adapted to its environment. Make sure it is getting plenty of deep watering, but that the water is draining. If water stands on the plant 30 minutes before it disappears into the soil, you have a heavy clay soil. Try mulching the root area, reducing the amount of water put on the roots each time, but increase the frequency. We would definitely give this tree another year or so, before it was eliminated from your landscape.

From Our Native Plant Image Gallery:


Sophora secundiflora

Sophora secundiflora

Sophora secundiflora

Sophora secundiflora

 

 

More Pruning Questions

Pruning Cuphea Plants
February 04, 2013 - The David Verity cuphea (cigar plants) that I planted last spring are now 3-4 feet high. I would like to move them, but before I do they seem to need pruning. All the branches are brown and dry lookin...
view the full question and answer

Sprouts at base of holly in Surprise AZ
November 15, 2010 - Friends have recently planted a holly tree in their front yard. They live in AZ and there is no grass (only rock) around their tree. It was planted as a fairly large tree (about 18 feet).My question i...
view the full question and answer

Young oak damaged by falling tree from San Diego TX
June 27, 2012 - My neighbor's Palo Blanco tree was struck by lightning and fell over our fence and on to a young oak tree in our yard. We waited a few days to see if the neighbor would offer help, but he never did,...
view the full question and answer

Buffaloberry from Grandma
June 25, 2008 - I have a "BUFFALO BERRY" that my Grandma brought back from South Dakota.It is approx.8yrs.old.All was well until this spring.It was budding out when we had a very hard freeze and got 3" of snow.Now...
view the full question and answer

Eradication of mahonia repens
July 27, 2008 - What is the best way to kill and/or remove mahonia repens?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2016 Lady Bird Johnson Wildflower Center