Hi!

Not sure the exact ID or age, but the darker green actually looks appropriate for this cactus. The new growth is neon green simply because it is new.

I am in the same area as you, eastern PA. That tiny growth is due to a lack of adequate light, it's called etiolation. It seeds a south to southwest window, at least. I find large cacti require LOTS of light, usually more than my southeastern Pennsylvania house can provide.

As for the soil, yours is way too old and way too dark. How often are you watering? The soil ideally would be a gritty mix (such as Al's gritty mix), or a very well draining cactus mix (50%/50% C&S mix and pumice/perlite at the least). In the winter, I water my cacti maybe once every month in winter, depending on their size, and once every 7-10 daysin summer when it is hot and dry.

Curious that the arm fell off. Once you repot (into a larger pot, as well as new soil) it may stand up better. Check the roots while it's out to make sure they're nice and healthy

I believe that OP is referring to a small growth on top - that may or may not be etiolated. Any ranch could get etiolated, not only new growth. Is it possible o get a close-up?

I also wonder why one of the branches broke off: was it knocked by something/someone, or just fell/broke off?

I don't know how you could manage this, but when you water, don't allow the pot to sit in that small dish which would have drainage water in it. Maybe you could lift it over to another pan of some kind for watering and move it back when fully drained, after some time.

Looks like Cleistocactus straussii. It is etoliated and needs stronger light. The growth is possibly a bud growing at the point where the growing tip of the branch may have died. A close up of this is needed.

Hi everyone, thanks for all the input. We repotted it yesterday into a slighter larger pot and new soil. We did a 50/50 mix of c&s soil with perlite. We weren't happy to see that upon taking it out of it's pot, it's rot are almost non-existent. I was quite worried when I saw that but somehow that roots it does have are white and healthy looking with some spots of new growth which is surprising but good. I think my boyfriend has not been listening to me about only watering it when the soil is dry and I think that's why it looks to be rotting at the base. So hopefully now that it's in much faster draining soil and he will only water when it needs it the cactus will heal from the root and be okay. I've attached some pictures of what it looks like and the small growth.

Small growth to the left is what I'm referring to. Do you guys mean the skinny yellow growth is from etiolation?

Scary roots and base ):

The arm fell off from it leaning so bad. The arm was going in a different direction from the cactus and it eventually became too much pressure on the arm's base. So currently, the cactus is in pretty bad shape but like I said, we hope that with it's new care it will get better.

@socks We could try that but it may be quite difficult to do that. The cactus and pot is quite heavy and with it leaning so bad we are afraid to move it around too much. I will see if it's possible to do that at waterings.

@ig Thank you for the id! I'm not sure though, I looked it up and that type of cactus seems to be more gray than this cactus is. These branches are pretty dark green.

The new growth is normal. Etiolation is from lack of light, and would happen to new or old growth - anytime plant is stretching to find more light. 3rd photo in your last post shows new growth turning toward source of light. Often ppl get excited to see plant growing fast & tall, but succulents, in general, are quite compact. In their natural habitat, they grow in sunny and relatively dry conditions, and these should be replicated as best as possible at home.

If any rot in plant, it should be get rid off as it may infect & possibly kill whole plant.

If pot is too heavy to lift after watering, consider putting 'feet' just below the pot to raise it. Sometimes, layer of pebbles (in the saucer, below the pot - not inside of the pot) will be enough. If it needs to be higher, there are clay pot feet available to buy. Or just cut 3 or 4 rings from a 1 - 1.25" plastic piping as high as needed. Or even buy plastic couplings from plumbing dept. (more $ & possibly too high). Even couple of bricks (if enough space) will work. Anything to raise the pot so it doesn't sit in residual water.

Keep plant at least by the window for more light 9may still not be enough), or even outdoors if warm (where are you located?-I don't see any snow :)

@rina Okay, so those skinny growths are from etiolation? Or the whole plant shouldn't be as tall as it is?

We potted it yesterday as it was- we didn't get rid of the rot. I did consider it but the base that is discolored wasn't soft and mushy nor did it smell bad or anything so I thought maybe it would be okay to let it go. Honestly, I was afraid of cutting that whole thing off and attempting to get it to root again. I was also hopeful since it's roots that are there show new growth and look relatively healthy to me.

I think we will try the pebble idea to raise the pot off the base, that seems doable to me. But now that I think of it, the saucer that it's in have little indents in it that are what is actually sitting on the floor, then the rest of it is flat. So it almost has wells in it if you can picture that. Do you think the water will run into those wells or would we still need pebbles?

We are located in eastern PA- so not terribly cold weather but we do have decreased levels of light now. We moved it to a window that gets good sun all day- so hopefully this additional sun will be enough. If not, we will need to find a different solution to it again.

No to "Or the whole plant shouldn't be as tall as it is?", sorry, maybe I wasn't clear. There are some signs of etiolation on it, but it should be growing tall comparing to some other species.

New growth could be from very top (as yours), or in some species branching along the stem. It also happens if the tip was injured, and new - or few- 'branch/branches' will grow.

This plant grows tall - columnar, I was generalizing about etiolated growth. I am sure this plant grew under different light conditions, as there are some thinner and thicker sections along the stem. What already grew will stay as is, and over all, not a huge problem. The recommendations received here are to give it lots of light, so it doesn't keep happening in the future. In the photo with 2 new 'tops, one is likely an offset (the rounder one). It could be a flower bud, but I can't tell from the photo. Other one seems to be skinnier, and perhaps is just continuation of the original stem/column? - I can't tell from the photo. One that is turning sideways also looks like continuation of original column. It is very skinny and etiolated, also growing towards the light (I believe that is what Alyssa was referring to as etiolated growth). Any new growth should be chubbier if receiving enough light.

Good example is the new column that grew from where the old one broke off: you can see that it is much thinner than others. Maybe the old branch was damaged, and possibly too weak that it broke.

Stem with roots is probably just corking - it happens with age on many cacti. I am going by what you said, that it is firm, not mushy - so it may not have any rot.

Keep watching the plant, and if you see any of the stems getting lighter, yellowish color and softer, or some black spots appearing, those are most likely rot. Cutting it off and re-rooting plant will be best in that case.

I know what you mean with the saucer: again, watch it. Another thing you don't want is water accumulating in small areas, sitting there for too long and become stale - heaven for fungus gnats. If it looks like its sitting there for a while, turkey baster could be used to suck it out. Just make sure bottom of the pot doesn't sit in water.

If you can, keep the plant outside when it gets warmer. Transition it slowly, direct light is much stronger than indoors. Start with shade, and after few days move into some more light.

I do not have this exact plant, and am not sure if it likes full sun or not. Research that eventually, and keep in appropriate light outdoors. Light thru the window is much better while indoors, and should not hurt the plant - unless very, very strong (I do not think it would be...)

The branch with the new growth on it that you have provided closeups of is a new branch. The thin stem beside it looks like it has died as I can see some brown colour at the base of it. This would explain why the new bud has formed as when you damage or cut off a branch, new branches form at the top of the damaged branch. The other thin sections on the other branches are due to etoliation.

I don't think it is C. strausii after seeing the closeups.

@rina So that discoloration on the base may just be normal? That would make sense since the roots seem relatively healthy. I will keep an eye on it for any rot; hopefully I don't see any though!

I think that saucer we have it in now will work but we'll try to make sure there's no standing water in the wells, it shouldn't be a problem. And we will definitely get it outside when it gets warmer! I think it would love that but like I said we live in PA so it'll take a while to get some warmer temps. I would love to do more research on this specific cactus but I'm still not sure what type it is! Do you have any guesses?

@sg Gotcha, that would make sense! Like I said, it's in a much sunnier place now so I'm hoping we won't have any etiolation moving forward. Do you have any other guesses on what it could be? I really wish we could figure it out! :/

I do not know cacti....but check out cleistocactus - it was mentioned before, and there are many species and varieties -look for them here-

Thank you, I will look into those and hopefully figure out what it is!