White Fly infesting Sweet Woodruff

I live in southern California (grew up in Germany). I love sweet woodruff and actually found somebody here who grows it. My problem is I have a hard time keeping white flies away from it, no matter what I do. What can I do to keep all the little pests away from it. It actually grows pretty well here, but I can not do anything with it, because by the time it is ready to simmer, chop etc....for recipes, it is loaded with white flies. I have tried soapy water, went to the nursery and got other stuff, but none of it worked. Can you help?

Since you do not have our winters that kill of the white fly during the freezing months, you will have a hard time with any poisons, because your plants will get re-infected from plants in the wild. I would suggest that you get rid of other plants that harbour these pests, so that you don't have any nearby source for re-infection. I do know they love tomatoes, cucumbers, celandines and scented geraniums. Check your garden to see where they seem to be congregating. Neem oil at the rate of 1 teaspoon per litre (quart) of water plus half a teaspoon of dishwash detergent or concentrated insecticidal soap can be used to get rid of a present infestation about a week before harvest. The juvenile hormone Enstar works really well, but may be hard to get.