It is a plant in the mint family, it is easy to grow (I have it in my back yard), it spreads like crazy. It contains something which makes cats get "high," or "drunk." The effect does not last, no harm to the cat. Humans can also eat it. It is great as a tea used prior to going to bed. Different effect on humans.

Cats eat it fresh - my Chestnut loves to go out in the garden and nibble, nibble, nibble! They also enjoy it dried. I dry my own, and then buy dried when mine runs out. I put some dried on the floor and they roll over and over in it!

I also put their toys in the canister and let them absorb the scent for a day or so then bring the toys back out.