Hakonechloa macra or Hakone Grass is a low growing, clump forming perennial that makes a gracefully arching mound shape that will ripple in the breeze.
It originates from Japanese mountain woodlands, so is best in cooler climates and does like a reasonable amount of shade throughout the day. It is perhaps best under trees in dappled shade or front to middle of borders, especially lining pathways in locations that do not get a lot of sun all day.
They also make a good edging to water features or waterways as they like moist conditions.
Altogether a very architectural plant that will get your visitors asking 'what's that plant?'.