Ginger

Zingiber officinale. A perennial root originating in tropical south-east Asia. Its roots extend greatly underground in tuberous joints, which are dried and powdered to be used as a spice. In Spring it sprouts a green reed-like stalk which is approximately 60cm tall bearing yellow-green flowers.

The spice is used vastly in Asian cooking, and in a lot of Medieval recipee, such as gingerbread (strangely enough).