En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Blackened leaves on purple sage in Utopia TX

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

Wednesday - December 08, 2010

From: Utopia, TX
Region: Southwest
Topic: Compost and Mulch, Diseases and Disorders, Transplants
Title: Blackened leaves on purple sage in Utopia TX
Answered by: Barbara Medford

QUESTION:

I live in Utopia Texas and have a 5-ft. Texas Purple Sage that has developed a black appearance on the leaves. What is this and what can I do about it?

ANSWER:

There are a number of different plants, mostly in the genus Salvia, that have the common name "Purple Sage." However, judging from the height you indicated, we are guessing that what you have is Leucophyllum frutescens (Cenizo). Without seeing the plant, knowing where it is planted in your landscape or what the soil is, we can only hazard some guesses, and you can use your judgment deciding what might be the problem.

You can follow the plant link above to learn about the preferred growing conditions for this plant. The first thing we would emphasize is that it needs very good drainage in the soil. In the first few months it is in the ground, it needs some deep watering, which is done by sticking a hose down in the soil and letting water dribble slowly in. If water comes to the surface when this is done and does not quickly disappear, the drainage is inadequate. If we are correct about which plant you are referring to, it does, indeed, grow natively in Uvalde County, so the USDA Hardiness Zone is appropriate for it.

If the plant is being watered by a sprinkler system, and especially if the drainage is poor, there is likely not only the drowning roots to consider, but a sooty mold caused by wetting the leaves. Also, the plant needs to be in full sun, which we consider to be 6 hours or more of sun daily. It will survive in part shade, 2 to 6 hours of sun, but will not bloom as well and, again, be susceptible to fungus.

If you feel the drainage is the problem, we would suggest you consider re-planting the bush. This is the right time of year for doing this, while the plant is semi-dormant. Dig a fresh hole, moving into more sunlight, if necessary, and add a good compost or other organic material. This will both improve drainage and enhance the roots' ability to access nutrients in the soil. Do not fertilize! This particular plant does not need fertilizer and you should never fertilize any plant under stress. After the drainage is corrected, a period of deep watering should be all that is necessary. Once well-established, the Cenizo is very drought-resistant.

One other possibility we will mention concerning the black appearance. Examine your plant for aphids. They excrete a substance called honeydew, on which a sooty mold can appear. They will not harm a healthy plant, but the appearance is unattractive.

From our Native Plant Image Gallery:


Leucophyllum frutescens


Leucophyllum frutescens


Leucophyllum frutescens


Leucophyllum frutescens

 

 

 

More Compost and Mulch Questions

Identification of shrub looking like honeysuckle in Odessa TX
October 02, 2011 - Bought a shrub in Pecos, TX yesterday. It looks like honeysuckle but the brightest flat orange I have ever seen. Flower and greenery looked like honeysuckle but when I looked on the Internet under or...
view the full question and answer

Frost damage to native plants in Austin
December 19, 2011 - Hello, We bought a number of native plants at this fall's WFC sale and planted them. The recent frost seems to have defoliated our pitcher sage, beautyberry, butterflyweed, and flame acanthus plan...
view the full question and answer

Smaller trees for limited space in yard in Austin
March 29, 2011 - Follow up to "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...
view the full question and answer

Planting Anacacho orchid tree in Llano, TX
October 05, 2011 - Re Bauhinia lunarioides: I'm trying to pick a good site in Llano Co for a 5 gal tree I received as a gift. Your plant database says part shade. The arid zone trees publication you reference in a...
view the full question and answer

Transplanting adventitious shoots of a mountain laurel in San Antonio
August 20, 2009 - Is it possible to transplant branches (shoots) growing from a mountain laurel that was chopped down? Some are two years old and several feet tall (but not yet blooming) and some as small as a foot. ...
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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center