En Español

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
8 ratings

Tuesday - April 26, 2011

From: The Woodlands, TX
Region: Southwest
Topic: Shade Tolerant
Title: Shade tree with non-aggressive roots for next to pool in The Woodlands TX
Answered by: Barbara Medford

QUESTION:

Hi Mr. Smarty Plants. We live in Spring, TX and are looking for a full-sun shade tree to plant in a large planter (about 6'x6') next to our pool. We want the tree to provide shade for our full afternoon sunny back yard, but also do not want an aggressive root system to damage the pool. Do you have any suggestions? Thank you, Kendra

ANSWER:

We don't want to be flip, but have you considered a large umbrella?

Roots of trees generally extend at least as far out as the shadow of the canopy of the tree. This area is referred to as the Protected Root Zone (PRZ). While a tree and its rootball would probably initially fit into your 6' x 6' planter box, the roots will quickly grow beyond it.  Additionally, the roots of the tree have the potential to damage/crack any concrete they encounter as they grow trying to reach water and oxygen.

We are frequently asked for "taproot trees," on the assumption that a root that grows straight down will not interfere with concrete walks, driveways, sidewalks and foundations. Alas, some trees do begin with a taproot but there are few trees with a true taproot; as time goes by roots will spread from that center root, both in search of water and nutrients and also as a base to stabilize the tree in the ground. A tree tall enough, and with comparable width to provide shade for your patio is going to have roots extending far beyond the initial planter, if either the tree or the pool survive the planting there. A tree big enough to cast shade, say, 20 ft. tall, will usually have about the same spread-20' wide. The roots beneath that tree will normally spread out from two to three times farther than the crown.

There are shrubs that might fit into that 6x6 space and not interfere with your pool, but they will not get big enough to cast appreciable shade.

 

More Shade Tolerant Questions

Groundcovers & Shrubs for Shade in North Carolina
April 30, 2013 - Mr Smarty Pants, My neighbor planted cypress trees as a border between his yard and ours and it is sucking up every drop of water and nutrient. We also have a purple plum in the area which creates ...
view the full question and answer

Choice of shade trees from the City of Austin
March 29, 2011 - I have a choice of three shade trees from the city of Austin. They are Live Oak, Elm, Cedar. Although I am happy to have a free tree, I think the choices are not the best for my home. I have a small ...
view the full question and answer

Ornamental grasses under desert willows from Dallas, TX
September 06, 2013 - I am planning on planting 3 desert willows in full sun, below the power lines at the back of my back yard in the White Rock Lake area of Dallas. I would like to plant some ornamental grasses in the be...
view the full question and answer

Deer resistant, drought and shade tolerant plants to go under oak tree in Austin
March 21, 2011 - What is the best deer resistant, drought resistant native plant to grow under my huge Oak tree? Grass does not grow. Will iris bloom?
view the full question and answer

Erosion control for a North Carolina creek side
February 29, 2012 - Hello Mr. Smarty Plants! I noticed a question on your website recommending NC native grasses and plants to help prevent erosion on a sloping backyard, including the use of an erosion blanket. The pl...
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 | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center