Jan 09, 2015 - 08:16 AM
Cultural and area modifications can sometimes help to remedy this problem too.
IGR's are not 100% effective. They are only 60-70% effective in most cases, and with flies, they can lay eggs and go through the life cycle in a matter of days. The 30-40% that does survive and is not effected by the IGR will quickly become more of a problem.
To answer your question, you can use Gentrol in your Greenhouse, but it has to be applied with a ULV fogger such as the Hurricane ULV Fogger. This fogger is also recommended to apply pesticides. You can also mix the Gentrol and Pesticides together to get better results. There is no magic bullet.