Nepeta cataria or Catnip is a summer flowering, herbaceous shrub that is good for cats and humans.
Cats love the smell of it and will rub up against it to get a short lived 'high'.
For humans it makes a refreshing and minty infusion to assist with stomach upsets and to help relaxation and sleep.
A natural repelant of aphids, it makes an excellent companion plant and is also useful against mosquitoes.