This is a great recipe for repelling White fly...

1 cup Soya Bean Oil 1 Tablespoon dishwashing liquid Place in jar and combine well. Add 30ml mixture to 1 lite of water and spray affected areas every 7 to 10 days until White Fly is eliminated. Repeat as necessary.

Another remedy is to put a teaspoon of Neem granules at the base of every plant. This is a systemic action which takes the Neem up from the plant roots.