Cheers Ronin. I am yet to find a solution for these super UK white flies but I may well give it a go next spring for my general plants.
An old codger who used to work in the greenhouses, where I worked for a while, said "if you can't see the other end of the 'house then you know you have a whitefly problem"
UKgrower, I can't see he dots. Sorry. eP.