Help please

[kan-kan]

Hello everyone,

I know this is a cactus related post, but someone advised me to post this here to have a better chance at getting an answer.

Two years ago someone gifted me a cactus and I don't know what specie it is. (I think it's an euphorbia but I'm not sure) It was perfectly fine until recently when it started turning brown. At first I thought it was root rot due to overwatering, but I haven't watered it in several months...
The brown parts start from the base and go up to the sides (where the spikes are), the center has yet to be affected on the upper part. They are hard and look very dry. There is also a weird black/grey round spot near the middle. You can see everything on the pictures (If they are not clear you can ask me for more).

Can anyone help me understand what this is? And how can I save my cactus? I would really like to save it.

Thank you for your help,
Kan.

[WayneByerly]

first, you are right. it's NOT a cactus. it's a euphorbia ... Euphorbia ammak to be exact. now the bad news. I'm not sure I can help you. Except with this. MONTHS is way too long to go between water sessions. While E. ammak can go long times without water, it's a plant ... it NEEDS water. My first suggestion would be to give it a good soak. RIGHT NOW. the wings of the stalks look wrinkled. The last picture really evidences that. and I cannot immediately think of anything that would cause that except lack of water. I have a couple of E. ammak specimens, and now, while it is hot, I water every two weeks or so. actually, I'm not sure that I go that long without watering them. I also know that I love them very much, which is the reason I've responded, despite my lack of being sure about what might be wrong with yours.

and another piece of bad news. even if it's just a lack of water and that watering it more often helps, it may not provide a solid FIX ... it might be that the damage that has been done MAY be permanent. but let's try the water first.

and what kind of soil is that? it looks like plain potting soil. I would also suggest that you re-pot the plant, using a soil mixture that is NO LESS than 50% pumice. mine is in a 80% pumice 20% organic mix and is doing fine. succulents are like cacti to some extent ... they don't like to just sit in wet soggy soil for long periods. they like a fast-draining soil.

where do you keep the plant? outside? in the full sun? has it been moved recently into the full sun? plants CAN be sunburned by suddenly putting them full sunlight from some other environment. I'm not sure what else I can say until I know that.

here's a picture of mine, and what yours SHOULD look like. the five arms are all THIS YEARS GROWTH!!!

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