Hello all,

First time posting. I have inherited a large indoor cactus. I'm not sure what kind it is...it may be a Mexican Fence Post, based on pictures I have seen but I could use some input.

I have some questions I could use some help with. Please see photos for reference.

Questions:
1) The cactus is growing taller, but the new growth is not the same width as the previous growth. I'm wondering if this is a natural occurrence or indicative of a problem. Could it perhaps need repotting?

2) There is some damage to the cactus...a hole of sorts (see closeup). I'm curious what is causing this and how I can prevent further damage.

3) there are some generally dry or damaged spots throughout on the sides.

Current care: I have been watering it every couple of weeks enough so that drainage occurs out the bottom.
It gets lots of southern-facing sunlight all day. Not using any type of fertilizer.

Thanks very much in advance for any advice and support!!

Harry

I can only answer #1.
1) The cactus is growing taller, but the new growth is not the same width as the previous growth. I'm wondering if this is a natural occurrence or indicative of a problem. Could it perhaps need repotting?

That is usual. See the part of the new growth that kinda "gets a bit skinnier"? Thats from not enough light.

But, it looks healthy

The hole and the brown spots look like physical damage, probably in moving to its new location. As long as they don't get bigger or soft it'll be OK.

Looks like cereus peruvianus

etiolated, not getting enough light

Thanks very much for the feedback! Strange about the light because it's right next to (though not directly in front of) a very large south-facing window. I will move it and see how that affects things.

The plant was not recently relocated, so not sure it's from physical damage. But I hope you are correct!

What matters most with respect to light is whether the plant can "see" the sun for hours a day. Not just the bottom, but all the way to the top. If the top remains in the shade, it will continue to grow skinny. This is increasingly difficult with tall cacti at this time of year because of how low the sun rises in the sky.

Interesting. Do you think it will get wider where it is currently narrow after being in the sun? It will look strange if it's wide, then skinny, then wide again. Thanks again!

No, the skinny part will stay skinny.

If I trim the cactus from where it starts to get skinny, would it grow back? Hopefully wider this time? Seems drastic but though I would ask.

It will branch at that point and the amount of light will affect how thick the new stems are.