One way to shift them, and very cheap too, is with a handfull of fag ends, soak in hot water, when cool strain the liquid, and spray. Simple, effective, cheap, readily available, and it will kill most pests - even people so I'm told, but I have not tested that.

One caveat, don't eat the plants untill a week has passed, by that time your 'organic' spray will have broken down and lost any nasty stuff.

Tim.