The nets can only keep out a portion of the insects. Outside the vegetable plots there are bottles of scented bait to kill moths, a natural biological means of controlling harmful insects.
網室可以隔離一部分飛蟲侵襲；菜田外還掛了誘殺飛蛾的「性費洛蒙」瓶子，以生物防治法防治病蟲害。