I'll have to try the lavender! I've never tried any sprays but I've heard garlic and lemon helps get rid of parasites. You'll here alot of people say that DE is bad for your lungs and a chickens and they think that if it can slice up mites like it does then what will it do to your lungs and your...
I do the same as you and I deep clean (such as scrubbing things down) about once 4 weeks to once a month. I always turn up there dirt about once a week. Sounds like your doing good! :thumbsup