Okay, a friend gave me some Pennyroyal this spring and it has spread all over in my garden. The thing is, I haven't a clue what it's used for. Anyone know what to do with it?

The use of the essential oils of this plant is not recommended and can be very dangerous. The link below has some information on what you need to know about this plant.
http://www.motherearthnews.com...

Thanks! Good info here!

I have grown both the upright and the creeping type. Both are very fragrant when stepped on, so you may want to position them where they will release their fragrance.

They kinda did that by spreading into the paths!