White flies can be eliminated by spraying with a dilute solution of
Rubbing Alcohol and liquid detergent. I would use about 1-2 ounces of
Rubbing Alcohol and 5 drops of liquid detergent into one gallon of
water. Spray the entire plant and get beneath the leaves if possible.
You may have to do this 2 or 3 times to disrupt the white fly life
cycle.
Another method is to liquify some "hot" cayenne peppers in a
blender. Filter this thru cheese cloth. Handle with care and wear
gloves! Add 5 drops of liquid detergent and dilute with water to one
gallon.
The liquid detergent helps the liquid adhere to the leaves and coats
the white flies.
You can also use natural Castille soap, instead of liquid detergent
but you should thoroughly dissolve it in warm water first so that it
does not clog your sprayer.

Nicky