Hi i have a few problems with my cactus 1. white crust on the tops it hard crust as picture and the cactus is turning brown where the crust is also 2. the needles are turning brown 3. should i be feeding my cactus 4. it has some sun bleach can i fix this
This looks both familiar and unfamiliar at the same time. There is webbing and white ... things that makes me think mite or mealy bug attack, but I think this needs higher resolution pictures to get a better idea of what it can be. If you mean that the thorns are changing colour from green to brown, then it is perfectly normal. Yes, these plants should be fed. Sun damage is usually permanent. It is not a cactus, but an Euphorbia.
