Totem pole cactus: not doing it right?

One benefit of having to bring so many non-hardy plants indoors for the winter is that I get to look at them a lot more than I did when they were out in the garden. One plant that I'm looking at a lot (and loving what I see) is the totem pole cactus (Lophocereus schottii f. monstrosus).

I picked up a small one of these a few years at the Missouri Botanical Garden, where the Henry Shaw Cactus and Succulent Society were having their annual plant sale. I was so excited to find one of these locally, as it had been on my want list for a while!

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Here's the plant when I purchased it in July 2013:

About 8" (20cm) tall, the two gentlemen I bought it from said that it would grow about 2" (5cm) a year -- in a really good year.

Today, two years later, I realize I must be doing something wrong.

Based on that math, this should be 8+2+2 = 12" (30cm) tall at most.

That photo above is a little misleading -- I tried using the panorama feature of my phone and things got a little distorted. Here's a single shot without distortion:

Topping out at about double that -- 24" (60 cm), I'm quite happy with how things are going!

Maybe mine will start producing arms this year, which means I'll be able to propagate this by cuttings -- apparently this form will flower but does not produce seed. I want to have multiple columns of this in a big pot!

With a maximum height of about 10' (3m) in-ground in a suitable climate, even if mine reaches 4' (1.2m) tall I'm not sure exactly how I'd overwinter this. At least it's not dangerous to move.

I love it, and love having it indoors for the next few months!


Do you grow this? Is the growth I'm seeing unusual, or is 2" a year an overly conservative estimate?

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