I have aphids and mealy bugs in my greenhouse. I have done almost everything to get rid of them. Neem oil,soapy water,alcohol and water,insect soap,and now by last effort ,I bought 4500 lady bugs and starting letting them go.
Re: I hate aphids we also had a greenhouse aphid infestation this year. I hope your ladybugs work for you... We were told by our local insect expert that the best way to control greenhouse infestation is to clear out all plant life for a minimum of 2 weeks, so the aphids have nothing to survive on and will die out. (You'd have to make sure any plants returned afterwards were bug free, of course!) The best time to do this is in the peak of summer, when you can close the vents and allow the temp to raise up as high as the greenhouse can stand (plastic may not like this). It wouldn't take 2 weeks to kill them off with intense heat, probably one would be plenty. In our case we had a crop that couldn't be removed, so had to deal with the aphids by culling a lot of plants and using soap on seedlings. We never did get rid of all of them, until the crop was over. They are indomitable creatures straight out of a horror story. Good luck, let us know how the lady bugs do...
