Explore Plants

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
    
 

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

Monday - June 22, 2009

From: Austin, TX
Region: Southwest
Topic: Watering, Cacti and Succulents
Title: Why are the leaves of my century plants yellowing?
Answered by: Jimmy Mills

QUESTION:

I am taking care of the Agaves (century plants) for my condo community here in Austin. They are planted in 18" or 20" pots. A couple of the plants have leaves that are yellowing around the bottom. At first I thought it might be under watering - I soak them once every other week for about two minutes. Now I'm starting to think it might be over watering. They are all lined up facing West and the ones on the north end of the line up are the ones experiencing the most yellowing. Any ideas?

ANSWER:

The term Century Plant is applied to eight different Agaves in our NPIN Database.  Since Agaves are adapted to surviving in dry environments, over watering is probably more of a threat in your case than under watering.

While some yellowing of lower foliage is normal in Agaves, this could be a case of salt burn which is a result of build up of soluble salts in the soil. Another sign of salt build up is the accumulation of a white residue on the outside of clay pots or on the rim of plastic pots and on the surface of the soil. This condition can be taken care of with leaching which in effect flushes the excess minerals out of the pot.

To accomplish this, give the plants a normal watering and wait  for thirty minutes to an hour. Then pour an amount of water that is four to five time the volume of of the soil in the pot, allowing it to drain through the hole in the pot. Discard the drained water, and wash out the saucer before returning the pot to it.

I'm including a link to an article on watering guidelines from  Colorado State University Cooperative Extension, and a link that describes the leaching process.

 

 

 

More Cacti and Succulents Questions

Spanish Dagger plant interfering with walkway in Ingram TX
April 09, 2010 - I have a Spanish Dagger that is now 8 feet tall and about to fall over in a walkway. Due to the danger of these very sharp tips I need to either cut down the plant or try to root in and replant. If ...
view the full question and answer

Native plants for highlights in a cactus garden
March 12, 2008 - Hi, I'm looking for some groundcover (succulents or herbs), shrubs, and other perennials to plant along with the cactuses (20 or so) I got from the CDRI plant sale in Fort Davis. The most important ...
view the full question and answer

Worms in non-native snake plant from Hillsborough NC
September 17, 2011 - I purchased a snake plant this summer for my screened in porch. I did not repot it and left it in the plastic pot in came it. I was about to repot the plant to bring it in and noticed there are worm...
view the full question and answer

Is Sedum recommended for a greenroof project in Houston
July 23, 2008 - Would you recommend using Sedum for a green roof project in Houston, Texas? Will the humidity effect the sedum? If sedum would be a poor choice, what would you recommend for Houston?
view the full question and answer

Replanting a blue agave in Rio Rancho NM
January 11, 2010 - I have acquired a Blue Agave, approximately 4-5 ft high. It still appears quite healthy. It was used over the holiday season for display purposes in a liquor store. Unfortunately, the root ball has be...
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.