Common name for Auxins which promote root growth.

"Rooting hormone" is one of a number of auxins - hormones which control plant growth and behavior.

Rooting hormones promote root initiation, growth of existing roots, and branching of roots. In horticulture, the auxins NAA and IBA, are often applied to the base of a cutting in order to promote root growth and improve the chances of survival of the cutting as a new plant.

Rooting hormones are typically sold as powders and are readily available in plant stores.

Use this tag for all questions about applying root hormones, and where the use of root hormone may be relevant to the question.