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?


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

Thursday - July 17, 2008

From: Round Rock, TX
Region: Southwest
Topic: Soils, Trees
Title: Effects of patio under large tree
Answered by: Barbara Medford


I would like to put in a patio under a fairly large tree. I understand a tree needs some open ground around it for air and water. Can I use flagstone leaving 6-10 inches of space between the stones? Or could I use something else like decomposed granite? Do you have any other suggestions?


Because this is the type of question that comes up fairly often, we would like to refer you to a previous Mr. Smarty Plants answer that covers most of the answers to your question. There are a number of excellent information links in that answer, especially one about permeable paving surfaces, which specifically mentions flagstones laid without mortar. It would seem that your plan would work, but you do need to remember that those roots are going to be pushing up to the surface for oxygen and water, and the more they push, the more the flagstones will be disarranged. However, if your patio plan is flexible enough to permit you to move stones around from time and time, and avoid compacting the earth, your patio should turn out fine.


More Soils Questions

Will wood shavings in the soil require nitrogen from Charleston MO
May 04, 2011 - I cut down a big maple tree and a lot of the wood shavings was left in the soil. I planted a flower bed over the area this spring. I later read that the wood chips in the soil would use a lot of nitro...
view the full question and answer

Need suggestions for planting trees in poor soils in Austin, TX
February 27, 2015 - Due to the clay soils and poor drainage in East Austin, what ornamental trees do you normally suggest?
view the full question and answer

My newly planted Mountain Laurel isn\'t doing well.
March 13, 2009 - My mountain laurel was planted from a container in Dec. It is in part sun, clay soil, and its leaves are turning yellow. should I move it or will that kill it?
view the full question and answer

Plants for steep slope in Pittsburgh PA
April 25, 2013 - I have a similar question to one from SC. I live in Pittsburgh, PA. We have a steep slope behind a newly built in pool. What type of plants can I put on the hillside to hold the soil. It gets a ...
view the full question and answer

Difference between soil moisture and water use from Austin
February 20, 2012 - In the native plant data base "growing conditions" can you explain the difference between water use and soil moisture?
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.
© 2015 Lady Bird Johnson Wildflower Center