I would appreciate your assistance with my cactus...(?Oreocereus celsianus)

I would appreciate your assistance

I live in Melbourne Australia.

This cactus is over 5 years old and as you can see it is not healthy.
It has been sitting on this south facing window sill for 3-4 years and perhaps 3 years ago seemed to change colour to a less healthy looking green. It then started growing this baby cactus about 1-2 years ago, and that seems to be growing upwards now, and the base of it has also changed colour. I water it infrequently, but may have done so more often than that over the last few years. The main reason I don't water it often is that it is in a wooden container that does not have holes in it (ie. no drainage).

Outside the window, we put up a shade cloth in summer and take it down in winter.

From my gardening experience, it is unhealthy and seems to be trying to survive by growing another portion. I originally thought it may have been growing the baby as it wasn't receiving enough sunlight, but now I am not sure if it is getting too much?? The colour change makes it seem like it's rotting, but it has been like this for 2 years and hasn't died yet.

From reading your website, my thoughts are to repot it into a pot with drainage. I dont know what medium it is growing in, so some cactus medium should help. Alternatively, it seems I can cut off the baby and replant it. Do I need to move it to a different position??

Your help is much appreciated as I would like it to survive!

Hello,

The plant had a big problem, the apex died. The apex is where is grows from.
So it created a new one, by growing a branch.
When this branch is bigger, something like 10cm, you can cut it to make a new plant, nice looking, and get rid of the old part.

Yann (France, Clermont-Ferrand). Serre tenue hors-gel + pleine terre un peu abritée. -10°C tous les hivers.

Hello,
is it useful to maintain this english forum when you read the rarely questions and the answeres (except Yann and some others) : pseudo "jesuistresstupide" which means " i'm very stupid" ?
Philippe

Thank you Yann! I will do that.

You must change its pot (ALWAYS make a hole in the container/pot), give it a proper soil while throwing away the old one in its entirety, clean the roots and cut the dead ones (and all the roots by at least half their length), let it dry for a few weeks and plant it again with the soil of your garden mixed with gravel and/or sand, with eventually a bit of peat.
Let it outside in Spring and never put it in your house again, even in winter : proven that they are in totally dry conditions, Oreocereus are very hardy plants (-15°C, or 5 F, or less)