Need help..Is my cactus rotting?

[senis]

Hi all,

I am totally new to all the cacti stuff. Last autumn I bought two cactus in a shopping mall. There were no names on them, but I think they were to differently grafted cacties. For a while it seemed that they were doing great. The top of one started to grow in the middle of the winter, and I was excited. So as I think of it now, I probably watered it a bit more then i should had..after some time I noticed that the stem of my growing cacti got softer and "thinner" and last week I noticed yellowish tint appearing and on weekend it went in brown mushy, smelly spots and eventually collapsed....

So now I got paranoid about the other cacti that's left, because one of it's stem edges got "thinner" as if there were no "cacti flesh" left inside in some parts, when I touch it..and it seems to be folding a little bit inside. Though the other parts so far seems quite ok. But I checked the base of the cactus, and found some grey-brownish spots on the part of the plant that is covered under the soil..one "spot" seemed to poke out of the soil already, when I checked on it after some time..so I took it off and re-potted...i googled somewhere that if the rotted part is not very big, you can cut on watering and re-pot it first.

Still, i am not sure if it is a rot at all, since the grey-brownish part is dry and not smelly...And after digging it out i noticed that on the grey-brownish part there is a crack in a cacti skin full of soil. There are some photos of my cacti before re-poting.

What could be wrong with it and what should I do next to save it?

Could anybody help a totally newbie how not to kill that beautiful cacti....


Many thanks,
S.

[iann]

It doesn't look like it is rotting. It might be a little thirsty. The photo of the dead one is obviously gone already, although quite possibly the top could have been saved.

You might want to try rooting down some pups from the top. They should grow roots quite easily and are quite manageable on their own roots (small pot!). The Hylocereus stock is vigorous but not very hardy and tends not to live very long.

Incidentally, the top growth in the second photo is not healthy. It is etiolated from too little light. The one you still have looks OK. Maybe it is getting enough light, or maybe it just hasn't grown.

[senis]

Hi Iann,

Thank you for the help!

Thirsty cacti was my second guess. But since I over watered my first cacti just thinking that maybe he is drying out, when he begun to "thin" and soften, I thought this time would be safer to presume that this one is rotting too And not to rush with watering.. Nice to hear that it seems to be ok. Since I have re-potted it already, I will wait then for a week or so and water it then. Though the new soil was a bit moist already.

As for the goner, I did cut the growing pups from the top and now they are still drying. However, I hadn't sulfur powder or any other powder at hand but I have read some advises to use charcoal for the cut while drying cacti so I applied some activated charcoal (this was the only thing most alike that I had at a time)..So I hope I haven't done much damage to them and they will live...