Here is a link with info on catnip:
http://www.sciencedaily.com/releases/1999/08/990827071500.htm
Says it repels german cockroaches. I know it’s great as a mosquito repellent.
“Today at the national meeting of the American Chemical Society, the world’s largest scientific society, Iowa State University researchers Chris Peterson and Joel Coats, Ph.D., reported that cockroaches are repelled by catnip – specifically, two forms of the chemical called nepetalactone, found in the catnip plant. Their findings could lead to the development of new natural insect repellents that could be sprayed along baseboards to keep roaches from coming out of the walls. “