Host an Event Volunteer Join Tickets

Support the plant database you love!

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Sunday - January 03, 2010

From: Hico, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Fungus on spineless prickly pear in Hico TX
Answered by: Barbara Medford

QUESTION:

Is there anything I can do to save my spineless prickly pear planted 3 yrs ago in rock garden. Pods had grayish-white fungus? on the pods and I noticed a few green colored bugs on them. Bugs are gone- but pods are drooping and falling off,like they have rotted and are mushy. There are several other cactus nearby and need help to save others? thanks

ANSWER:

This is almost surely a moisture-related problem. Even in a rock garden, your Opuntia ellisiana (tigertongue) is probably being subjected to more watering than it can tolerate, and perhaps without sufficient drainage. You need to remember that these are desert plants, accustomed by millennia of experience to growing in fast-draining sand (when there was any rain water to drain) and surviving. They are succulents, holding moisture inside their structure, but moisture collecting around their bases or soil that is too moist will encourage fungus. To protect your other plants, you need first to remove the pad(s) that are appearing rotted and mushy; in fact, it might be necessary to remove the whole plant. This will help prevent the spreading of the fungus to other cacti near it.

You next need to address the amount of water that is being applied to the garden, either by rain or artificial irrigation.  You say you planted your rock garden three years ago; this may be the first time since it was planted that it has received very much rain. Since Central Texas is unexpectedly getting some rain this Fall and early Winter, it's possible that poor drainage is causing that water to collect. Under no circumstances should your Opuntia be receiving supplemental watering. At this point, if the drainage in your rock garden is insufficient to protect the roots of the cacti, there is not a lot you can do about it. If and when plants have to be removed because of the problem, you can replace the soil with a more sandy mixture specifically for the growth of cacti and other succulents before you re-plant. And don't fertilize. These are native plants that can get along just fine with the materials in the soil where they live. Fertilizing will only encourage fresh growth, which is going to be more prone to disease. 

From our Native Plant Image Gallery:


Opuntia ellisiana

Opuntia ellisiana

Opuntia ellisiana

 

 

More Diseases and Disorders Questions

Rust-colored spots on Lantana?
June 05, 2009 - Mr. Smarty Plants, I live in Cibolo TX and my lantana plants are about 3 years old. They have done exceedingly well until this spring. The leaves have developed brown, rust colored spots and the le...
view the full question and answer

Rust on Amelancier Foliage in PA
February 03, 2015 - I live in Pennsylvania and have been plagued with a rust on my serviceberry (Amelanchier canadensis) trees over the past few years. I am unable to find very much information on this disease on the we...
view the full question and answer

Insect infestation of plants, dog and home
September 14, 2008 - I have plants that some kind of bug is killing them, my fan plam, ficus tree and other plants. The leaves are drying up and falling off. Apparently, they also are infestion my apartment. I feel them c...
view the full question and answer

Dealing with live oak suckers in Central Texas
March 05, 2015 - Hi, I have a couple huge Live Oak trees in my back yard. Trunks are 4' in diameter. These Live Oaks produce a lot of root sprouts/suckers. I had always head that a tree's roots feed on water/oxyg...
view the full question and answer

Wisteria with root rot in Flower Mound, TX
July 11, 2009 - I have a wisteria that is showing rot root from an exposed wound on the side of the base. Would like to save the tree. What can I do to fix the problem.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.