I recently got this little cactus from the clearance section at a local grocery store. On its label, it just says it's an ordinary summer cactus. When I got it, I did notice some slight orange spots but now one side of the cactus is orange. Can anyone help me ?

Photos?

Here

Probably got overwatered and sat on standing water at one point then exposed to very cold temps. :shrug:

How does the orangey side feel? Is it firm or does it seem soggy? If it is soggy, hmm, not sure..maybe time to do emergency cut, to save the other side that is still okay. But keep fingers crossed..it is risky time..
still way too cold right now

tarev said: If it is soggy...

keep fingers crossed...

Agree.
Unusual question for winter....
But did it perhaps get sunburned on that side? Sometimes sun exposure it's not used to getting kills the cells on one side of a plant.

If your Christmas Cactus is turning orange (or another color), it's due to stress.

The soil appears dry but that one side of your cactus appears wrinkly and soggy, which has me thinking that rot has occurred but I'm not at all familiar with the desert type of Cacti.

Sometimes, succulents may create a callus line, thus effectively protecting the healthier side. But it all depends how deep and far along the rot has set in.

So that was the reason I was asking if that orange part continues to feel soggy. If so, as last measure, then slice off all the rotted part and, apply a light dusting of cinnamon as fungicide, keep it warm and air dry it for as long as it takes.

It will be a long wait and risky just because it is winter. Be very patient, and good luck

The orange tissue looks dead.

Hamwild said: The orange tissue looks dead.

I agree, looks rotted and wrinkled.