En Español

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 - May 12, 2013

From: Clovis, CA
Region: California
Topic: Diseases and Disorders, Cacti and Succulents
Title: Black rot at center of Agave from Clovis CA
Answered by: Barbara Medford


We have some beautiful variegated "Green & Cream" Agave plants in our cactus garden. One in particular has done quite well for several years and is the largest, about 18" tall & across, it has never flowered but has put out many "babies" which we have replanted and grown in abundance. The problem is with this largest plant it has begun to develop a black soft rotting spot along the center leaves before they unfolded and has grown slowly throughout the spring. we think it is a fungus of some type. There is no evidence of bugs and it is NOT powdery more slimey looking. So far it is the only plant affected. Help?


We are stumped on what species of Agave is the "Green and Cream." We do not have any Agaves in our Native Plant Database that are referred to as "variegated" nor that appear to have cream color edging or stripes. We hunted around the Internet and found this article and picture from San Marcos Growers of what they referred to as Agave parryi 'Cream Spike.' The article says it originated in Mexico, which would put it out of our realm of expertise. However, there is an Agave parryi (Parry's agave) in our Native Plant Database which is listed as being native to  Arizona, New Mexico and Texas. As you can see in the picture below from our Image Gallery, there is no trace of cream on this plant. The name "Green and Cream" is no doubt a trade name dreamed up by some creative plant retailer to attract sales, but it does make it hard to identify.

However, we have answered other questions on diseases of Agave. Please go to this previous Mr. Smarty Plants answer and follow the links in it; hopefully this will give you some clues. This refers to Agave americana (American century plant), but both are agaves and supposedly susceptible to the same problems.


From the Image Gallery

Parry's agave
Agave parryi

More Diseases and Disorders Questions

Yaupon in bonsai failing to thrive in Lufkin TX
July 16, 2009 - Hi,I have a yaupon that I've turned into a bonsai. It's been producing new vegetation until about a month ago. Then all of a sudden the branches started drooping and the leaf tips started turning bl...
view the full question and answer

Oak root resistant hedge for Southern California
December 28, 2013 - I live in Southern California and my cypress hedge has oak root fungus. What kind of hedge can I plant that will grow fast and be resistant to the fungus?
view the full question and answer

Mexican Lime Turning Yellow
March 25, 2015 - What causes moderate yellowing of 40% of the leaves of an 8 year old Mexican Lime Tree that is booming and blooming right now with lots of thick new growth? I used a general garden fertilizer a few ...
view the full question and answer

When is it time to remove diseased oak trees in Belton, TX?
May 03, 2013 - When to give up on my live oaks. We lost/mostly several live oaks since 2011 and the drought. One, died from the crown, one large mass at a time, and now resembles a 10' totem pole with scraggly gro...
view the full question and answer

Powdery Mildew on Monterrey Oak
July 30, 2015 - Monterrey oak developing gray-white patches on some but not all leaves leading to wilting. could this be powdery mildew? Tree not stressed. Thanks. Best treatment?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center