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

Sunday - October 07, 2007

From: Austin, TX
Region: Southwest
Topic: Soils, Shrubs
Title: Potting soil recipe for azaleas
Answered by: Barbara Medford


I have a couple of Azaleas in pots that need repotting.I can't remember the recipe for the medium I put them in last time other than pine bark mulch. I think there were three ingredients. What is your recommendation?


Even Mr. Smarty Plants can learn something new. We thought something as exotic-looking as an azalea must surely be a sub-tropical non-native. But, a search in our Native Plant Database turned up 26 native varieties. Not that it has to be native to be grown in a pot, of course, but at the Lady Bird Johnson Wildflower Center we try to concentrate on the care and propagation of plants native to North America. Turns out that azaleas include not only natives to North America, but we found 3 native to Texas! Among the other things we learned is that all azaleas are rhododendrons but not all rhododendrons are azaleas. We learned that wild azaleas are found on every continent except Africa and South America, with Southwestern China and Papua New Guinea having the most species. They have been hybridized for hundreds of years, and in the U.S. the natives do best in the Pacific northwest where rainfall is plentiful and winter temperatures are not too low. For more information, go to this site on Care of Azaleas.

But that's not what you asked, was it? You wanted a recipe for potting soil for containerized azaleas. On the above-mentioned website, we finally found a recommended recipe. We don't know if this was the one you were thinking of, but we hope so. It calls for equal proportions of peat moss, vermiculite, potting soil and coarse sand.

And, since we found those Texas native azaleas, let us tell you about them. They are Rhododendron canescens (mountain azalea), Rhododendron oblongifolium (Texas azalea), and Rhododendron prinophyllum (early azalea), pictures below.


Rhododendron canescens

Rhododendron oblongifolium

Rhododendron prinophyllum





More Soils Questions

Hybridized Indigo Spires having problems in Wimberley, TX
August 19, 2010 - I planted 7 Indigo Spires from one gallon containers in May and now each plant is about 18" tall. 4 of the 7 fell over about 2 weeks are. The plants still look healthy with no dropped or curled leav...
view the full question and answer

Is the Obedient Plant a bog plant?
August 16, 2008 - I purchased 2 obedient plants at a farmer's market in Michigan. As I was unfamiliar with this plant, the merchant told me it did well in full sun. It was just what I needed. When I got home I look...
view the full question and answer

Growing Native Plants in Juniper litter from Wimberley, TX
October 04, 2010 - Junipers create an environment under their canopy that prohibits growth of other plants. I have a virgin lot that has been cleared of many juniper but has remaining heavy natural leaf mold containing...
view the full question and answer

Destructive landscape crews in The Woodlands TX
October 20, 2012 - Hi. We need help. We recently moved to a house where landscape crews have been blowing away the leaf litter from the front yard for many years. The underbrush was also cleared long ago. The result...
view the full question and answer

Problem With Vegetable Garden Soil
June 09, 2013 - We live in Liberty Hill on 25 acres and we are working to restore native grasses and plants. We are ardent supporters of the Wildflower center. I say this because my question is not "typical" of wh...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center