Various Questions About Fairy Castle Cactus

Question

I have a few questions about my Fairy Castle Cactus. It’s barely grown since I bought it, in contrast to my other plants. I’ve read conflicting info about the amount of light it likes. I’m using the right soil, not overwatering.

So, why are the joints growing in a spiral like/twisty fashion? It’s not a very attractive plant right now but I’m giving it time to grow, lol. If I prune it a little, will that help it or just damage the plant?

Also, I’ve read the “fake flower” could be real with the glue actually being cactus sap? I dont know if there’s any truth to this. And, the flower, opens and closes by itself. So how could it be an inert thing? I’d be suprised if a fake flower still reacted to the environment like that. Please help me understand!

Answer 1

One thing I can say with absolute certainty is that that flower is fake. Acanthocereus/Cereus cactus don't flower until they are 10 years old or more and the flowers look like this...

Add to that they fact that Fairy Castles very seldom flower according to what I've read. There is debate as to whether Fairy Castles is a good species (Acanthocereus tetragonus ssp. uruguayanus or a monstrose version of Acanthocereus tetragonus. If it is monstrose, that would explain the lack of flowering even in mature plants. I've always assumed it was monstrose.

Your plant looks like it's growing to me. Note the lighter colored spines at the ends of the branches, those are new spines. As they age, they darken. As mentioned above, these are a very slow growing species, and growth is hard to discern.

Spiral growth in cactus is not well understood. Some say it's a reaction to stress. A discussion of the theoretical mechanism is here:

Spiral Growth

So, follow the growing advice above and be patient, that fake flower will fall off eventually.

Pruning this plant won't do it harm. Use a sterile, sharp blade (wipe the blade with alcohol). You could try to root the cuttings, if you need more of these.

Some Cereus species have beautiful flowers, but the plants themselves are kind of meh, in my opinion.

Answer 2

This plant likes full sun, so if it's not getting enough sun, that might explain the twisting you're seeing. It's not that unusual for a stem or two to twist, but yours does seem a bit extreme. It does not appreciate draughts much either, prefers to have an environment that is not frequently disturbed by air changes, and does not like to be near heat sources such as radiators.

In regard to the flower, if it's real, they open at night, so if yours is opening and closing, it might be a real flower. Fake or real, it will eventually drop from the plant anyway. Apart from the twisting, the plant does not look unhealthy, but if its not getting enough sun where it is, try to find somewhere it will get more. It's not growing so fast as your other plants because it is simply a very slow growing plant, it does not mean there's something wrong. It is not necessary to prune it, it will not help anything, though if any part of it develops rot, pruning that out is quite a good idea. https://www.gardeningknowhow.com/ornamental/cacti-succulents/fairy-castle/fairy-castle-cactus.htm