I grew some 5' plants outside, just beautiful girls!, and placed screens overhead as someone told me that would change the heat and UV (or whatever the term is?) so they wouldnt be spotted from over head? It was a wonderful grow and I wish I still lived there. My set up looked like a screen room to keep bugs out. I never did see any spotter planes, so I dont know if it worked, but the plants sure didnt suffer, and might have been good for them as the sunlight was really intense. you can get sliding glass door screens for almost nothing at a re-store (habitat for humanity store) so thats what I did. thanks!!