This is Nepeta from the Lamiaceae family, more commonly known as one of the many Catnips! 

It consists of loose, aromatic foliage that, as the name suggests, cats love! The chemical compound that attracts and affects cats is nepetalactone. If eaten it acts as a sedative, if smelt, well they simply go crazy.

This particular Nepeta has purple-blue flower spikes arising in the summer. The flowers are tubular with 2-lips, some completely purple and some with blue and dark purple colouration. 

Accompanied by this fuzzy bumblebee 🐝 (Bombus hortorum) and my Grandma at The Wynyard walled garden.