What type of fertilizer do you use on a rosemary bush and when is the best time to fertilize?
Fertilize a Rosemary Bush
Certified GKH Gardening Expert
I would not use fertilizer on rosemary (or most herbs). The reason being that fertilizer will cause rapid growth and the plant cannot keep up with producing the chemicals that create the flavor at the same rate as the growth. It results in a less flavorful leaf on the plant which means a poorer quality herb for cooking.