Hi John, I can only offer what we've used to get rid of a bad white fly infestation with our potted ficus trees we have outside. This was recommended at a local nursery here in SoCal and has worked well. Just google "worm castings for white flies" for more info.

Thanks chloebud! Very interesting. I’m just now noticing several articles about worm castings being a solution to whiteflies. So cool, I didn’t know that.

We also didn't know about worm castings. In addition to using them, I would spray the leaves with the hose a couple times a week. The nursery also recommended something called "Eight Insect Control" that you can spray on. I used it too but have found just the worm castings and hose work for the ficus trees.

A hand crafted blend from the Old Farmers' Almanac to control and discourage whiteflies: In a 32-ounce shower bottle blend 2 sections scouring liquor, 5 sections water, and 1 tablespoon fluid cleanser. Shower the blend on the foliage of nursery plants that are helpless to these nuisances.

Bob Tanem in Northern CA (Sunday morning KSFO radio show) has for years said that he uses old coffee grounds after you make your morning coffee.

-Babka

https://www.bobtanem.com/recipes-for-pests-and-diseases

Solution #2: This is my favorite organic solution: Place 2 lbs of old coffee grounds in one gallon of water. Bring to a boil, cool and run through a coffee filter. Spray on infested plants.