Blast with the hose on high pressure or spray with a mixture of eco-friendly washing up liquid and water. Next year either make your own garlic spray or buy a proprietary one this will keep the white fly at bay.

Thanks for that Moon Grower,I'm on a allotment so can't spray with a hose,but have tried with a sprayer.This eco-friendley washing up liquid,do they sell it at Supermarkets.

Me again Moon Grower how do you mix your Garlic Spray.

They sell Ecover at supermarkets but you might want to go to a GC for horticultural soap.

Garlic spray. take your complete head of garlic and put in a blender with enough liquid to make a pulp, you can also add a few chillies. Blend for a goodly amount of time, strain off the liquid and dilute one in ten as a spray. This is a systemic and will deter the white fly etc. for several weeks. Spray once a fortnight as a preventative measure. You wont smell it within seconds of spraying but the insects will and they do not like the smell! Will also deter cabbage white butterflies from laying their eggs!

Thanks again Moon grower,you have been very helpfull.

Hope it all works Rwh

Got some Eco Friendly washing up liquid from the super market,have sprayed twice and greatly reduced the fly,will spray again next time i'm at lotto,thanks again for info Moon Grower.

Good to know it worked.