Erica Vale Seeds - Catnip Available Australia Wide When to sow All year round sowing Germination Easy (14-28 days) Description: Nepeta Cataria. Hardy perennial. Height 45-90 cm. Cats love catnip with true passion. Sniffing the highly aromatic foliage's minty scent produces waves of ecstasy, playful behaviour and a happy almost trans like state. It is a healthy stimulant and cats suffer no ill effects. In fact it can be used as a positive training aid. Try sprinkling some dried leaves in a new bed or where you want the cat to go. When to sow: Indoors - all year round. Outdoors - Spring, Summer and early Autumn.