There are several things
which can cause a white appearance on houseplants. Probably the most common
problem is mealy bugs, a soft bodied scale. These attack houseplants usually at
the joints where leaves are attached to the stems, or along the veins of the
leaves. It looks like little cottony patches. Mealy bugs can be controlled by
dabbing each one with some rubbing alcohol, and repeating this in a week, or
spray with a pyrethrum or insecticidal soap. Spider mites can cause the leaves
to look mottled and white, and should be very gritty to the feel. When large
populations build up, tiny webbing will occur. Resmethrin or a pyrethrum should
control these. The third option, and not as common is powdery mildew which
is a disease. The entire leaf surface is covered in a white substance that rubs
off. Sprays of a general fungicide such as daconil or funginex would control
this, but I doubt this is the cause.
I have a white
fungus or something on my houseplants. What do I need to spray they with to keep
it off?