Welcome to ATP, Terence. If you could please post a picture of the white growth, that would help us a lot to tell what you have going on.
I have Clivia here, and have never had anything show interest in it, but I think I'd better go check on them. We have every bug and fungus here . . but I did have a white insect infestation on the backs of the leaves of my pepper plant. It turned out to be a clumping whitefly infestation, and I just wiped it off with a damp cloth, and then sprayed the plant with a soapy water solution, 1/2tsp. dish soap to a liter of water. (be sure to hit all surfaces of the leaves, and rinse off with water before the sun hits the plant) Evening is a good time of day to do this, no sun, and often the morning irrigation or rain rinses the soap off for you.