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

Thursday - April 07, 2011

From: Austin, TX
Region: Southwest
Topic: Shrubs
Title: Knife Acacia or Shrubs for Austin
Answered by: Brigid & Larry Larson

QUESTION:

Hello, Do you know if knife acacia is a suitable plant for North Austin? Does it have sharp leaves or thorns? How large and full does it get? We are looking to replace our existing pampas grass plants.

ANSWER:

Mr Smarty Plants approves the removal of Pampas Grass, since Cortaderia selloana, commonly known as Pampas Grass, is a tall grass native to southern South America, and is an introduced species.   On the other hand, Acacia cultriformis (Acacia knife) is native to Australia.  It’s named that because it’s leaves have an unusual triangular shape, like a knife blade or shark fin.  Reports varied in the 12-16 foot region for both height and width.  So, we're not supportive of that selection either, as not only is it non-native, but it is also listed in weedwatch as a potentially invasive species.  

  From your description, I would expect that you are looking for a tall grass or mid-height shrub.  The Wildflower Center mission is to encourage the use of native plants and there are many to choose from.  In my search I found three different varieties of Sumac:  Rhus virens (Evergreen sumac), Rhus aromatica (Fragrant sumac), and Rhus glabra (Smooth sumac).  Other attractive species include Erythrina herbacea (Coralbean)Eysenhardtia texana (Texas kidneywood) and Bauhinia lunarioides (Anacacho orchid tree).

                   
Rhus glabra
                      Eysenhardtia texana                  Erythrina herbacea  

  These were found using the recommended species page for Central Texas and looking at the shrubs 6’-12’ in height.  Depending on what you are actually looking for, you could review these or other recommendations and find some attractive and suitable plants to replace the Pampas grass!

 

More Shrubs Questions

Problems with azaleas
April 22, 2008 - Last summer I planted 10 evergreen Azaleas "Hino Crimson" I sprinkled a little rhody fertilizer in their holes before planting and gave them plenty of water all summer. They are all doing fine excep...
view the full question and answer

Roses for Austin soil
May 01, 2014 - What roses would work in the soil near Lake Austin Spa?
view the full question and answer

Full Sun, Wind-Tolerant Shrubs and Vines for Steep MN Hillside
June 26, 2013 - My neighbor and I share a very steep, large (in total almost 200 ft. wide) west-facing hillside in Excelsior, MN on Lake Minnetonka. We both have a flat grass area at the bottom so the hillside does n...
view the full question and answer

Moderate-sized trees for lawn in West Virginia
August 10, 2014 - I recently had a landscape design completed by a professional lanscape company. The landscape is sloping down in front of my house. At the corner they included a Sweet Bay Magnolia, which we like ve...
view the full question and answer

Wintering a Lemon Cypress tree in Eagan MN
September 29, 2009 - I Have a 2 1/2' Lemon Cypress Tree. I'm wondering if I can leave it outdoors for the winter, if not, how would I winter over indoors?
view the full question and answer

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