We love this herbaceous perennial. Relatively new to the retail world, this plant will get larger than what is stated on most labels, so site accordingly.
By mid spring, the emergent foliage is rapidly unfurling, and is an intense chartreuse. As the seasons progress, the intensity fades with heat and stress, to a softer light chartreuse/green. We've seen plants (part shade, rich moist soil) get 84" tall and as wide. Often the plant will be shorter than this, but if you into force feeding your plants, this will give you some pleasure.
Best sited where protected from wind, with some afternoon shade, but too much shade will stunt the plant. Definitely irrigate during a prolonged dry spell.