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 - September 28, 2008

From: Iredell, TX
Region: Southwest
Topic: Pruning, Trees
Title: Pruning native Senna lindheimeriana
Answered by: Barbara Medford

QUESTION:

I asked a question about pruning a Texas Senna tree. The Texas Senna I have is either a S. wislizenii or a S.lindheimeriana. It is a beautiful tree that I purchased at a Texas Native Plant nursery. Like I said in my previous email, it is about 7 to 8 feet tall and and about 7 feet across. It has small green leaves and is very bushy and full. My question was how and when do I prune it. Can you please give me some information on this?

ANSWER:

Oops, sorry, you're absolutely correct. Our mistake was to look for the "Texas Senna" in our Native Plant Database, and it wasn't found under that name. The "Texas Senna" we did find was a non-native. This is the problem we run into when retailers name their plants without regard to botanical names. Fortunately, you apparently got (and saved) a label with the proper botanical name.

Senna lindheimeriana (velvet leaf senna) is a tender perennial and considered a sub-tropical herbaceous plant. Senna wislizeni (Wislizenus' senna), on the other hand, is referred to as "shrubby", has thorns, and can apparently take lower temperatures. 

We did not find any pruning instructions for either plant; however, we did learn that in colder temperatures, Senna lindheimeriana (velvet leaf senna) will die back, but will come back from the roots. For that reason, we would suggest that you let it run through its blooming season (apparently October is the end), and then trim it back pretty thoroughly. When we prune a plant like that, we always leave stalks sticking up 8 to 10 inches, just so we'll know where it is. If you are expecting some pretty cold weather, it would be a good idea to mulch the roots. The plant should begin to come back from the roots in Spring, and will probably grow bigger and more lush for having been trimmed back. 

If you believe that what you have is Senna wislizeni (Wislizenus' senna), we would still recommend pretty good pruning, but maybe not down as low. And, in fact, you might want to wait until late Winter, when you don't expect any more hard freezes, to do that pruning. If you prune it too soon, and there is a hard freeze, it could damage new growth starting to emerge. 

 

From the Image Gallery


Lindheimer's senna
Senna lindheimeriana

Lindheimer's senna
Senna lindheimeriana

Canyon senna
Senna wislizeni

Canyon senna
Senna wislizeni

More Trees Questions

Viability of Texas Mountain Laurel in Florida
March 12, 2008 - Dear Mr. Smarty Plants While visiting Pinnacle Peak in Scottsdale we saw a beautiful Texas Mountain Laurel tree. What are the chances of this surviving in the Ft. Myers, Florida area. Either in t...
view the full question and answer

Looking for a redbud sized tree to plant in Tulsa OK.
September 27, 2011 - I am looking for a native tree about the size of a redbud to place in my prairie bed in Tulsa Oklahoma, wildlife friendly trees preferred, thanks!
view the full question and answer

Keeping a Texas Madrone alive from Belton TX
October 01, 2012 - I have found a supplier of a Texas Madrone and have been wanting to grow one ever since our family vacation to Big Bend NP. My question is how do you have success with this tree? Many people say it is...
view the full question and answer

What are the green round growths on the edges of my oak leaves in Fairfax, OK
May 21, 2013 - round growths on the edge of oak leaves. ranging in size from a pearl to a lime. ranging in color from pale green to lime green. hollow, small ones appear to contain one small gnat sized seed. the la...
view the full question and answer

Non-native peanutbutter tree suckering in Oregon City OR
August 02, 2011 - I have a beautiful 'peanutbutter tree' in my yard. I have noted that there are plantlets coming up that appear to be attached to the main root(s) of the tree. I have been breaking them off as I don...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center