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

Friday - July 01, 2011

From: Austin, TX
Region: Southwest
Topic: Watering, Trees
Title: What fertlilizer for live oaks under drought conditions?
Answered by: Guy Thompson


In your June 7 answer about helping live oaks survive the drought, you state that additional fertilization may help as well. What kind of fertilizer to you recommend and how should it be applied? Thanks.


Tree specialists don't agree on a particular type of fertilizer, one recommending  13:13:13 (nitrogen:phosphorus:potassium), while others just say a "standard" fertilizer will suffice and still others do not mention fertilization under drought conditions.  Mr. Smarty Plants suggests an organic nitrogen (slow-release) fertilizer such as 8:2:4.  Follow the instructions on the package, but apply a fairly low amount of the fertilizer around the trees near their drip lines.  Too much fertilizer could promote new leaf formation - not good in drought times.  If the trees seem to be relatively healthy you might well delay applying the fertilizer until September, which is the normal time.

Make sure you don't use Weed-N-Feed fertilizer.  This has a herbicide that kills broad-leaf plants, including oaks!  Water the fertilizer in well after application. Hopefully there is some sort of mulch of leaves or other plant material on the soil to help retard water evaporation.

And pray for a good, slow rain.


More Watering Questions

Fungus gnats on house plant in Edwardsville IL
July 16, 2009 - I recently purchased a Trailing Perennial Plant, and I am seeing a lot of gnats flying in my house. Could this be the problem?
view the full question and answer

Failure to thrive of desert willow in Wimberley TX
August 10, 2010 - I have a desert willow. It is always, whether I water it or leave it alone, yellow/ brown leaves, dark spots on the leaves, losing leaves. now it looks sad and not very healthy. Can you please tell m...
view the full question and answer

Dry browning leaves on Monterrey Oak from San Antonio
August 08, 2013 - I have a Monterey Oak that was planted four years ago and was doing great until the last two weeks. It has turned brown and the ends of the branches are very dry and brittle. The root flare was cov...
view the full question and answer

Daily water absorption of live oak from soil
December 04, 2003 - How much water does the live oak absorb from the soil per day?
view the full question and answer

Will chlorinated pool water affect the soil in a vegetable garden?
May 22, 2009 - For the first time I'm going to plant a vegetable garden, and I have an area cleared. My swimming pool cover came off over the winter, and the pool water is a dark green to look at, but looks clear w...
view the full question and answer

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