Question

Monkey Tail   QUESTION: Hi Will,

Your answer to my last question was great so I'm back on here for another one. I have a monkey tail cactus (or that's what I understand it to be) which is not doing well at all. Many of the stems are beginning to dry up and die. Back in the summer when we first got it most of the tips seemed to dry out along with some of the stems. At that point it began to grow new little shoots off many of the stems. Now it's much worse. As I said, many stems drying out and even the new little shoots on some of them. There is also some white spots on it. They are very dry and thin. And resist being scratched at with a knife (I tried this to see if it was scale).

The plant is hanging in a north west facing window that gets a moderate amount of light. It is right over the heating vent (unavoidable if it is to get any decent light) but is also close to a bit of a drafty window.  I have been watering it about once every two weeks. Am I giving it too much water? When we first got it we were watering it very little as I assumed being a cactus that's what it would like. Then I read somewhere about it needing more water, so started to give it more.

This is my boyfriend's precious plant and he's desperate that it not die!!!

Thanks, Will for any help you can give. :)

ANSWER: Hi Aislinn,

Your plant is more commonly called Rattail cactus, but its botanical name is Aporocactus flagelliformis.

This is not an easy plant. It is native to Mexico where it grows with its roots attached to tree limbs or in tiny cracks in rocks. That means their roots are adapted to receiving brief bursts of water and then drying quickly. The roots are also small and quite weak and that makes it hard for them to adapt to pots.

The primary problem for yours is that it has not been getting adequate light. This plant requires direct indoor sunlight for most of the day. It should be in a south or west window that is completely uncovered. It should not be hung so high that the top of the plant is above the window. Room temperatures are fine.

Yours should be planted in a very sandy potting mix that does not retain water for very long. Water it thoroughly and then wait about a week. Push a stick into the soil to try to determine if the soil is dry at least half to two-thirds of the way deep into the pot. When it is that dry, it is time to water it again. If in doubt, err on the side of dryness.

To be on the safe side, take some 2-inch long tip cuttings, let them air dry for about 24 hours, then set the cut ends upright in a cactus potting mix that is kept barely damp. If kept in a warm, sunny spot, these cuttings will root quite readily and you will have a new plant, just in case.

If your plant recovers and thrives through the summer, you may be able to get it to flower in the late fall. In the fall, reduce the watering somewhat and allow night temps to drop to 55-60 degrees F. until buds emerge along the stems. After buds form, keep temps at about 70 degrees and resume normal watering.

Good luck with this challenging plant!

Please let me know if any of this is unclear or if you have any additional questions.

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Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC



---------- FOLLOW-UP ----------

QUESTION: Thanks, Will. The potting mix it's in does not appear to be that sandy. It retains it's moisture quite well. What do you think about me transplanting it into cactus soil at this point? Or just leave it alone in terms of that until it recovers (hopefully!!).

Thanks again!
Aislinn

Answer
Hi Aislinn,

Given the fragile nature of this plant's roots and the tenuous condition of your plant, I do not recommend transplanting. Improve the light, allow the soil to dry deep into the pot and when you do water, add just enough that the soil is very dry again in a week or so.

I cannot guarantee that it will recover. It is possible that the reduced light and heavy soil have already caused enough root damage that it will not recover. That said, it is certainly worth a try by following my recommendations, including taking some cuttings now.

~Will