Help! I think my cactus is dying

[Flyover]

I've had this cactus for 7 or 8 years. I usually water it a lot less over the fall/winter, and it usually goes dormant which involves getting "skinny", and when I start watering it more in the spring it bounces back. That's what usually happens.

This year it hasn't bounced back, and has continued looking emaciated, and is starting to look floppy and yellow, with a few brown spots I'm worried about.

Anyone know what's going on? (Sorry, not sure why the pictures are rotated...)

cactus 1.jpg (75.22 KiB) Viewed 1504 times

cactus 2.jpg (61.83 KiB) Viewed 1504 times

cactus 3.jpg (61.5 KiB) Viewed 1504 times

cactus 4.jpg (69.79 KiB) Viewed 1504 times

[BryanT]

It's an Euphorbia. Looks like Euphorbia ammak.
It's a big plant for a relatively small pot.
You might want to remove it from the pot, and check the root system for any rot or dead root or possible root bound.
If is root bound, you can cut back some of the root, leave it rest to dried and healed for few days, then repot it into a bigger pot with fresh soil. It should recover if no rot.
If it already rot in the stem, then you will need to cut back all the rot area, and try to regrow from cuttings.

[BryanT]

From the picture, the plant seems doesn't get enough light.

[Flyover]

It's an Euphorbia. Looks like Euphorbia ammak.
It's a big plant for a relatively small pot.
You might want to remove it from the pot, and check the root system for any rot or dead root or possible root bound.
If is root bound, you can cut back some of the root, leave it rest to dried and healed for few days, then repot it into a bigger pot with fresh soil. It should recover if no rot.
If it already rot in the stem, then you will need to cut back all the rot area, and try to regrow from cuttings.

Thanks! I will do those things (hopefully I'll get time this week).

As for light levels, it's in a south-facing window in my 3-season room and has been there for years doing great.

[jerrytheplater]

Rot does not wait. You should not either. This is a high priority job. Not kidding.

[greenknight]

Check out this post on a similar problem:

viewtopic.php?t=40860

[Flyover]

Check out this post on a similar problem:

viewtopic.php?t=40860

Thanks! That was interesting, hopefully useful.

[Flyover]

Just to follow up:

About a week ago I finally had a chance to re-pot the cactus into a larger pot. While I did so I tried to get a peek at the root ball but it felt like as I was brushing away dirt little bits of root were breaking off too so I didn't do it very aggressively and left most of the dirt still on it. I also pruned off a sickly-looking limb.

Now the cactus is looking better: no longer emaciated, and green replacing yellow color.

Thanks again for all your help, everyone.

[greenknight]

You shouldn't worry about losing a few roots, they grow back quickly. If you saw healthy roots, though, that's the main thing. If you're adding new soil that's the same as what it was potted in before you don't need to remove all the old soil.

The results speak for themselves, sounds like you did okay.