white spots that wipe off then reappear a few days later

Question

I have a dragon plant directly in line with my air conditioner/heat unit and
it keeps getting white spots that wipe off on the top of the leaves. What
is it and should I move the plant?

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Answer 1

A/C units are notoriously bacteria and fungus ridden. This looks like either downy mildew in early stages, or powdery mildew.

Powdery mildew will be much easier to cure: https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm

Downy mildew can be a bit tougher: https://www.gardeningknowhow.com/plant-problems/disease/downy-mildew.htm