The only thing I've used thus far is neem oil spray. that has worked WONDERS on the white flies. I have also been releasing white fly parasitic wasp eggs and green lacewing eggs AND ladybugs into the garden. the green lacewings and ladybugs have very efficiently dealt with the pests and the white flies really decreased as soon as I got out the neem but I suspect the natural predators are why they've stayed gone.
