What Am I Doing Wrong With My Cactuses?

Question

Hello. I have quite a few cacti and recently have had some that have died. They have all have some weird signs that I wasn’t able to find anything about on Google. I’ve attached pictures, but some have orange spots, some have rotted from the bottom (and had pink or orange on the inside). I’m not sure what the problem is but I don’t want it to spread to the rest of my plants. I water them once every two weeks and there is a humidifier in the room with them. Any help would be appreciated!

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Answer 1

This is soft rot which is caused by the bacteria, Erwinia. This is usually introduced in a few ways. Overwatering, which it sounds like you do hold off on, is the most usual culprit. I don't think that this is the case, here. The next is infected tools. This could be a likely cause if you have pruned or cut lately. The most likely thing that I would consider is the humidifier. Humidity makes a suitable breeding ground for the bacteria. True cacti prefer and are accustomed to drier conditions. They won't appreciate humidity, which makes them highly susceptible to disease.

You will hate to here this, I'm sure, but there are no cures. Prevention will be key to stop spreading. This means eliminating humidity, keeping any dead materials away from any of your cacti, and cleaning utensils between each use. This may help:

https://www.gardeningknowhow.com/ornamental/cacti-succulents/scgen/erwinia-soft-rot-in-cactus.htm