Share 'Help for "buggy" lettuces'

I have really good luck growing lettuces in my earth-boxes (truly, not an add for them - I can put them in the shade and in partial sun in Phoenix.) BUT they end up being FILLED with bugs. I do not want to spray with chemicals of course. It requires so much cleaning and water waste that I have not grown them for a while. I tried: 1) Garlic and Cayenne in h20 spray, 2)Soapy water spray (yuck), ...