I have been very successful with lady bugs to eat the white fly. Buy them in a little box of several hundred at a garden center (Armstrong's here). Release them in early evening after 20 minutes in the refrigerator. Then when they get out of the container they don't all just fly away.I HATE white flies!!! It's almost impossible to get rid of them.
I have also tried the Veggie Gardner's organic pesticide and it seems to help too. I also have a fence around my garden so they don't dig up my plants at this time but the hoppers in our area come from the fields and hop into our yard so they're able to grab them and eat them outside of my garden area. I also have my son do a grasshopper round up and give them to the chickens while the chickens are in their coop..that method works very well plus it gives my son the chance to help out with the gardenI have chickens but need to fence around my plants so they don't dig them up or eat them!