Plant Doctor Archive

Catnip leaves turning purple

Question COULD you tell me why my potted catnip has now gone a reddish-purple colour? It is in a sunny spot and watered, but is looking very limp.

Answer WE are not quite sure why this is happening. You don’t say how old your plant is, but as they grow older, they do become scraggly. After flowering, you must cut off the plants 10 to 12 cm above the crown before they turn brown. This allows regrowth from the buds located on the lower stem nodes. Being a perennial, it will grow back year after year.

Catnip prefers a well-drained soil in a sunny or shaded position. Water only when dry and feed every fortnight with a well balanced organic fertiliser.