(Nepeta cataria) Perennial. This staple is a voracious ground cover, growing up to 2 feet in height. Yes, cats LOVE it, but it is also a wonderful, gentle herb for humans, especially children. For us, catnip has quite the opposite effect; calming the nervous and digestive systems. Enjoy Nepeta as tea whenever you feel the need to unwind. Approximately 200 untreated catnip seeds.