Commonly known as Greater Quaking Grass or Rattlesnake Grass (my personal favorite) among other names, this north African-Eurasian native is a fairly easy to grow but attractive ornamental in the garden (and if you really want to, you can eat the leaves and seeds...though they're not much for flavor). Clumps of slender leaves may reach 18 inches tall, topped in one to several spikes of inconspicuous flowers that give way to their hops or rattle-looking seedheads with overlapping scales, which hang freely and flutter in even soft breezes. An annual in most places, it will happily re-seed however anywhere it's decently moist and well-drained.
Available plants are shoots around 6-9 inches tall.