White fly reduction

Sorry if this is posted elsewhere,
How do i "organically" reduce my white fly population. The little * are attacking My brassicas.
Many thanks.

Do you mean in the greanhouse or in the ground ?

Yellow stick papers in the greenhouse .

Brassica Whitefly doesn't cause much damage so you can ignore it.  You can wash them off with a hose if the plants are big enough or you can a non-orgaic or organic spray.  There is information about these on the RHS site.

http://www.rhs.org.uk/advice/profiles1100/cabbage_whitefly.asp

I like to use Enviromesh as it's close knit to keep out everything cept rain and sunlight. You have to fit it close to the ground though to keep everything out. Saves using chemicals though so has got to be a good idea. Fleece works but it gets blown about and pecked at by pigeons