Collinsonia canadensis

An impressive and little-grown lamiaceae from North America - tall, with broad lush leaves - almost indistinguishable from some good forms of Hydrangea arborescens. The amber-yellow flowers top them off nicely in late summer/autumn. 

Good in dry shade and chalky soils and flowering when little else is. A fully hardy and easy-going woodlander that should be much more widely grown.
£10