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

Saturday - July 13, 2013

From: Wallingford, CT
Region: Northeast
Topic: Pruning, Problem Plants, Trees
Title: Will catalpa roots damage a nearby swimming pool?
Answered by: Guy Thompson

QUESTION:

Will a catalpa tree cause problems to my swimming pool? It is 8 feet away and I cut all the branches off every fall. It then grows back to about 6 feet in diameter an makes a great garden feature but I am worried if it will hurt my pool. It is about 9 years old now. Thanks so much

ANSWER:

Most arborists would say that 8 feet is too close to your pool.  But I have not read of any case of damage to pools or house foundations by catalpa roots.  However, both the Catalpa speciosa (Northern catalpa), which I expect you have, or the Catalpa bignonioides (Southern catalpa) have extensive root systems.  My biggest cause for concern is whether your pool may have a hairline crack, leading to a slow seepage of water in the direction of the tree.  Tree roots tend to grow strongly in the direction of any water source.  So the first step is to inspect the pool for possible leaks.

I would suggest that at the time that you trim branches off in the fall you also dig a trench parallel to and about two feet from the end of the pool.  Trim off cleanly any tree roots that are growing towards the pool and bury some kind of root deflector to prevent roots from growing past that point.  These deflectors, or root barriers, can be found advertized on the Internet.  I have myself found this particular product to be sturdy.  Few large roots would grow towards the pool at a depth exceeding eighteen inches, so your deflector should extend to two feet below the surface.  To further reduce the chances of root problems, restrict any hand watering of the tree to the side away from the pool.

You are already aware of the positive and negative attributes of Catalpa trees. Trimming off the branches does prevent the dropping of seed pods during the winter.  With care you should be able continue growing your tree without harm to the pool.

 

From the Image Gallery


Northern catalpa
Catalpa speciosa

Southern catalpa
Catalpa bignonioides

More Pruning Questions

Repairing damage to Anacacho Orchid Tree in Austin
April 30, 2008 - Hi You Guys!! We have an understory Anacacho Orchid Tree in the front and my sweetie was trimming the big oak and dropped a branch down, splitting one of the large branches off the Anacacho. The wou...
view the full question and answer

Getting a senna to fill out from Irvine CA
May 30, 2013 - I have a Senna of some kind, started from a seed by a friend. I got it as a small,six in high) seedling. After two years it is now blooming beautifully, but is a single thin stem 4 feet tall with ve...
view the full question and answer

Cutting back a Rhododendron in Maryland
June 17, 2015 - I have a planting of six shrubs across the front of my house (alternating azalea & rhododendron). All have died except for one huge rhody & a small azalea next to it. Can I cut the huge rhody back to ...
view the full question and answer

Cutting back perennials in PA
July 25, 2011 - Can you pinch back echinacea in the spring to produce a shorter plant? I have some that get too tall and fall over.
view the full question and answer

Trimming native salvias in January
January 17, 2008 - I have heard you can trim Hot Lips, Raspberry and other salvias back severely in January, to about six inches from the ground. Is this correct?
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