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
2 ratings

Friday - April 09, 2010

From: Austin, TX
Region: Southwest
Topic: Septic Systems
Title: Plants for a septic field on a steep slope in Austin
Answered by: Barbara Medford

QUESTION:

My septic field is on a fairly steep slope and is overrun with bermuda grass, native grasses, vines, thistle and other vegetation. What types of wild flower seed can I use on it that will grow on a slope and yet not send out deep roots that will impede the septic field workings?

ANSWER:

Please read this previous answer, also on septic fields in Austin. Your requirements do not totally duplicate those on the previous answer, but it will give you a good place to start. Excerpted from another previous answer:

"So far as we are able to determine, there is no list or database on root lengths of any plants, including natives. The root length of any plant is variable, depending on the plant size, genetics and age as well as environmental conditions. Keep in mind that when your system was designed, it was a well-known fact that something would grow over it-if not planted by you, then weedy volunteeers. If those volunteers are not eliminated, some of them are bound to be woody plants, and that's what you're trying to avoid. 

All the research we consulted agrees that the best plant material for the earth covering septic systems is grass. They have fibrous roots and will help hold the soil in place, help prevent erosion on your slope, conduct some of the moisture to the surface of the soil, and are easily maintained. Wildflowers will fall into the same category, particularly the annuals. The one thing you want to avoid is woody plants, especially trees, as they develop long roots that stretch out beyond the canopy of the tree and would go for the moisture in the septic lines. Those roots can certainly clog the lines, so keep the trees and shrubs away."

Something that would be really nice for the area is a Meadow Garden. See our How-To Article on Meadow Gardening. Because you already have plants you do not want, particularly bermudagrass, we also suggest you go to our How-To Article A Guide to Native Plant Gardening, paying special attention to the "Soil Preparation" portion.

Most of what you need to know has already been covered in the material from previous answers and the How-To Articles. But, just so we will earn our (non) pay, we'll list a few wildflowers and grasses that we think would be good for your site. Please realize that sowing the wildflower seeds should not be done until Fall in the Austin area, and that just throwing out seeds is not going to control the vegetation you already have there. In fact, it works the other way around, you have to first control the non-wanted plants before you seed, or most of those wildflower seeds will never come up.  We will go to our Recommended Species section, click on Central Texas on the map, and then select first on "herbs" (herbaceous blooming plants) under General Appearance and then, on a separate search on "grasses and grass-like plants." Another option is the Lady Bird Johnson Legacy Wildflower Mix, if you want to try just throwing out some seeds and see what comes up. There are also a number of plant suggestions in the Meadow Gardening How-To Article. Follow the link of any plant you are interested in and learn whether it is annual or perennial, size, light requirement, etc.

Native Grasses for a Septic Field in Austin: 

Muhlenbergia lindheimeri (Lindheimer's muhly)

Muhlenbergia reverchonii (seep muhly)

Nolina texana (Texas sacahuista)

Schizachyrium scoparium (little bluestem)

Herbaceous Blooming Plants for a Septic Field in Austin:  

Callirhoe involucrata (purple poppymallow)

Coreopsis lanceolata (lanceleaf tickseed)

Echinacea purpurea (eastern purple coneflower)

Melampodium leucanthum (plains blackfoot)

From our Native Plant Image Gallery:


Muhlenbergia lindheimeri

Muhlenbergia reverchonii

Nolina texana

Schizachyrium scoparium

Callirhoe involucrata

Coreopsis lanceolata

Echinacea purpurea

Melampodium leucanthum

 

 

 

 

 

 

More Septic Systems Questions

Native flowers for Door County, Wisconsin
September 02, 2009 - We recently were required to put in a new septic system on our vacation property in Door County, WI. This left us with a clearing on our wooded lot where the septic field is now located. The installer...
view the full question and answer

Will a 10-ft. yaupon damage my septic lines in Texas Hill Country?
July 18, 2009 - A 10 foot yaupon is growing in my Texas hill country septic field. The field pipe is 5 feet below the surface. Should I be concerned about the roots invading the pipes? What would be the best way to r...
view the full question and answer

Tree roots vs. leach field in Heber Springs AR
February 03, 2010 - We need shade in front of our west facing house; however, our septic system and leach field are there also. What kind of fast growing trees can we plant that won't ruin our septic system?
view the full question and answer

Length of root systems for wildflowers over septic system
March 29, 2009 - Mr. Smarty Pants: I want to know the length of root systems for native Kansas wildflowers that will be planted on a Wisconsin mound septic system, which is a special septic system partially above grou...
view the full question and answer

Native plants for septic system in Massachusetts
February 04, 2009 - What native plants can grow on a septic mound safely for the septic system?
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