white fly

I started square foot gardening last year, my other half built me raized beds, and portioned them all off, everything went really well untill the dreaded white fly, it covered everything. I was hoping the winter would see them off, but no such luck, I have winter cabbages cauliflowers and kale still growing strongly, but still covered in white fly.  can anyone suggest a green method to get rid of them.  thanks

Bunny Guinness back last October on Gardeners' Question Time recommended Neem Oil. It is an organic control for flea mite on plants and pets (she apparently uses it to wash her dog) but also works on whitefly. There are loads of stockists on search engines.

Hope this works for you