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?

Share

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
1 rating

Wednesday - April 22, 2009

From: Tonto Basin, AZ
Region: Southwest
Topic: Problem Plants, Cacti and Succulents
Title: Eliminating agave roots in Tonto Basin AZ
Answered by: Barbara Medford

QUESTION:

Greetings Mr. Smarty Plants, from Tonto Basin, AZ! We have numerous mature (huge!) Agave Americana plants here, and have, until recently, enjoyed them. However, we are now ready for a drastic landscaping change. We're in the process of cutting them down, and would like to know if there is any way to kill the trunk on these plants. Our experience has been that if there's a minuscule section of root remaining in the ground, countless "pups" will eventually re-appear. As we would like to completely and permanently eliminate the ones that grow right next to our house, we are asking about killing the root. Thank you in advance for any help you can provide! Happy gardening!

ANSWER:

While we hate to recommend herbicides, you are correct that a small piece of root will generate fresh agaves, just what you don't want right now. We know you don't want to hear this, but digging them out with a good sharp shovel is the best way to begin. And disposing of them is going to be tough, too. Please don't put them in the compost pile, those thorns can last forever. A long-handled shovel, long heavy leather gloves and maybe heavy pruners to kind of cut the job down to size are going to be necessary. The best suggestion for cutting them down and keeping them down that we have found so far is to get some glyphosate herbicide and a few disposable sponge brushes. Don't go wild with this, because you want that area to be hospitable to your new landscape, so no spraying or drenching the soil. When you have removed all the root you can by manual (as in labor) techniques, make a clean slice across the remaining root and, within 5 minutes, paint that open wound with the glyphosate, full strength. You have to do it right away, because the agave, like all other survivors, will quickly move in to heal that cut over before the herbicide can get to the rest of the root. You will still get pups popping up over time, and waiting a while before you put in the raised beds is a good idea.

And, lesson for the future: When the pups pop, get them out while they're little. Get it all out with the same sharp shovel if you can, and do the paint job on any root remaining.

 

More Cacti and Succulents Questions

Trimming of dead foliage on trunks of yucca in California
December 21, 2008 - There is a Yucca plant in the back yard. I want to know how to get the old foliage that has died off of the trunks, it looks kind of ragged. The foliage is about three feet from the green. Can you ...
view the full question and answer

Bloom stalks on agave plants
September 26, 2007 - Hi, We have Agave plants in our garden for years. But in the past few weeks, we noticed a giant asparagus looking thing growing out in the middle of the plants. We don't know what it is, but every d...
view the full question and answer

Skin Reaction form Cochineal on Prickly Pear
February 16, 2015 - I have severe burning and peeling skin on pads of fingers after touching "white stuff" on a prickly pear. White stuff tuned purple then burned skin even after washing hands. Skin has been cracking a...
view the full question and answer

Removing faded flowers from plants in Georgetown, DE
July 28, 2012 - I bought a chamase rose quartz that was in bloom. now the buds are dead, should i remove them or just leave them on the plant. they wont just fall off. and the tips of the plant has new growth.
view the full question and answer

Which cactus grow in the Eagle Pass, Texas area?
May 11, 2009 - I would like to know which types of cacti grow in my area since I can't seem to find any websites that may give me a way to identify them. The type I seek is the round type of cacti not nopal types. ...
view the full question and answer

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