I have a few cacti which I keep indoors and since the weather has been hot and sunny a couple of them have shrivelled up and died very suddenly (I think they rotted from the bottom up). I'm not sure why as I've had them for a few years now and they always looked reasonably healthy. I don't think I under or overwatered them either!
Before I lost my first cactus, I kept them in my room (where I thought they would have enough sun) but gradually introduced them to the kitchen window recently which gets a lot more light than my room as I thought this would help them keep healthy. Since I moved them another one has rotted and now I am very worried about their health!
I've noticed that one of my cacti has these orangey brown spots over it.
Also, this guy has wrinkly light green/brown growth down the bottom with white-ish green lumps. It doesn't look very healthy to me but it doesn't seem to be rotting.
Are these things something to worry about? If they are, what can I do? I really don't want to lose any more of my cacti as they mean a lot to me. Any help would be very much appreciated!
Many thanks,
Caitlin