Jim its been around probably since before I was born (just kidding). A lot of orchid growers used to use it which is how I came onto it. You can sterilize tools, put directly on plants, and use on benches, pots and walls. I don;t use bleach on the inside of the GH because of the plants, but also because I read a long time ago that it can react with the polycarb and cause a gas to form that is toxic
