Expert: Maureen - 3/2/2010

Question
QUESTION: My cactus has had a slight indentation on one side for the past year or so.  We had a very bad freeze and I brought it into the garage for protection and covered it.  When we brought it out, I noticed that the indentation was worse and it is also indenting on the other side.  The top looks relatively healthy, but I'm not sure what to do.  Can this one be saved? and if so, how???  (I also lost a 6-foot cactus with the arms also).

ANSWER: Do you have a picture?  I'm not sure what you mean by an indentation.  Is the area soft, discolored?  Do you know the name of the plant?  I need to know where you live, the type of soil the plant is growing in, etc.  I don't want to misinform you, so that information would be helpful.  In the meantime, don't water it.

Maureen

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QUESTION: Maureen, I do have a picture that I will send.  By 'identation' I mean that it looks like it's sinking in.  
The area is indeed discolored and somewhat soft.  I think it's some sort of barrel cactus, but not sure.  I live in the Pacific Northwest, Vancouver Washington and the plant is in a terra cotta pot, which it has been for some time.  Thank you very much for any help you cn provide.

ANSWER: It appears that the bottom is rotting. The discoloration and softness would support this. There is no way to stop rot at this stage.  It may well have started a year ago.  It usually begins in the roots and the plant, tho dying, looks perfectly healthy. What I would do to try to save this plant is, with a sterilized knife,slice across the plant about 1 inch above where the tissue looks healthy.  If you see any discoloration or soft tissue, slice again with the knife sterilized until you only see healthy green/whitish vasculature.  Let that callous for 1-3 weeks.

You might want to look at the roots of the plant just to see what rot looks like.  Throw that away along with the soil as it is all contaminated and sterilize the pot if you want to use that again.

To re-root the healthy plant, pick a pot not much bigger than the plant.  Mix up half builders sand and half peat if you have it, and just bury the calloused end deeply enough to keep it upright.  Put in an area of filtered light and WAIT.  Don't water it, just occasionally mist. I've had cacti take as long as a year to reestablish.

While waiting, buy yourself another little plant to keep it company.

good luck.

Maureen

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QUESTION: Maureen, thank you so very much for the sound advise.  I'll keep my fingers crossed that it takes hold.  While the plant is callousing, do I just leave it sitting out?  Does it need to be in the sun and/or should I place it so the bottom is upright?  I've never calloused a cactus before.  Also, when I do repot, should I use any rooting hormones?  Again, thank you.  Oh, could you tell from the picture if this is indeed a barrel cactus?

Answer
Yes, just sitting out (inside) in partial shade.  You can leave it on it's side.  Some folks use rooting powder and some think it slows rooting.  I tend to brush it on while the plant is callousing just to protect it.  The important thing is to put it in clean medium and resist watering.  You do have a barrel cactus, a beauty.  There area thousands of species but I believe the Genus is Notocactus or Echinocactus.  Sometimes they are synonyms for each other. If you Google either you'll be able to see thousands of pictures.  The spines on your's are distinctive as they curve in so that will help. I can't get to my cactus literature because I have a broken foot but I will save your picture and when I can walk again I'll see if I can be more specific.

Good luck and keep me posted.

Maureen