Piet Oudolf
Piet Oudolf (Dutch pronunciation: [ˌpit ˈʌu̯dɔlf]; born 27 October 1944) is an influential Dutch garden designer, nurseryman and author. He is a leading figure of the “New Perennial” movement, using bold drifts of herbaceous perennials and grasses which are chosen at least as much for their structure as for their flower color. (Wikipedia)
“For me, garden design isn’t just about plants, it is about emotion, atmosphere, a sense of contemplation. You try to move people with what you do. You look at this, and it goes deeper than what you see. It reminds you of something in the genes — nature, or the longing for nature.”
– PIET OUDOLF
Piet Oudolf featured on PBS News Hour
Oudolf public gardens around the world
Hauser & Wirth, Somerset, UK 
The High Line, New York City 
Lurie Garden, Chicago 
Maximilianpark, Hamm, Germany 
Pensthorpe, Norfolk, UK 
Vlinderhof, Utrecht, NL