I have known something was wrong with my two night-blooming cereus for a few years. I saw the dried, shriveling leaves and dark foliar spots. I was painfully aware that they hadn't bloomed in well over a decade. (Yes, a decade!) But I convinced myself it was too much water, too little water, too much light, too little light; I refused to honestly size up the problem. And now my denial might cost me the plants entirely.
It's anthracnose. At least I'm fairly certain that's what is destroying the mother plant (a passalong from a very dear mentor who has since passed away) and the cutting I made from it. After some research in my books and online, I found the dark, depressed lesions and defoliation match uncannily with the pictures and descriptions of anthracnose, a group of fungal diseases that seem to typically affect deciduous trees and vegetables but that apparently go after poorly cared for houseplants too.
I blame myself not only for letting the infection get out of hand but for the shoddy care that let it get established in the first place. Irregular watering and too little air circulation allowed the plants to get stressed and hence left them vulnerable to this fungus.
(A little crowded, perhaps?)
Now I'm left trying to root the handful of leaves that appear to be disease-free, while I must throw these beloved keepsake plants in the garbage (not even a dignified, circle-of-life burial in the compost!).
The pots, scissors and surrounding plants that were likely exposed to spores all need disinfecting. And after dithering for about two years, I will finally repot, divide, fertilize and care for my remaining houseplants! It is only now, in the harsh light of regret, that I can see how unhealthy they really are.