how to get rid of white fly?

just been cutting some of my broccoli and found one was covered with white fly, and also one of the cauliflowers in the next row.

is there any easy way to get rid of them? ideally cheap and organic would be ideal.

will they spread through the rest of the crop? if so is there anything i can do to discourage them?

thanks all.

You could try soaking tomato leaves in water and sprayinhg them,dont know if it will but ive heared butterflies and caterpillars dont like it

I'm not sure what can and can't be recommended due to the legality of "home-made remedies". Nobody has mentioned spraying with a natural soap solution, so maybe you can't do that any more, but it used to be raised on here as a good way of getting rid of pests. I noticed on an American site that earthworm humus is recommended. Apparently the plants take up whatever's in it and whitefly don't like the taste so they move on to other pastures (possibly your cabbages or sprouts).

By the sound of it, if you adopt a chemical solution (soap or other) or even just spray with water, you'll have to keep repeating the treatment to get rid of the several generations you could have on the plants (adults, larvae and eggs).

Personally, I haven't found whitefly does a significant amount of damage. Unattractive, but just water keeps them down enough not to bother the plants too much. What I have noticed is that if I do manage to get rid of whitefly completely, grey mealy aphids move in and they are far more of a problem for my plants than the whitefly.

thanks for all the suggestions.

think i'll keep washing with water for this season just to keep them at bay.

look into planting marigolds and / or making a tea from them to try and keep them away in the future.

thanks again all