Just wondering if the Hermes lavender sachets are an effective moth-deterrent. I'd hate to one day find my silk or cashmere scarves with moth holes in them. How many would I need, per square metre? Lol! Ok, maybe I'm getting a bit technical but how many do u generally throw around in a cupboard, for eg? If find these sachets not really effective, pls share which methods you employ to ward off moths.