Piet Oudolf (born 27 October 1944, Haarlem) is an influential Dutch garden designer, nurseryman and author. He is a leading figure of the "New Perennial" or "New Wave Planting" movement, using bold drifts of herbaceous perennial plants and grasses which are chosen for their structure as much as for their flower colour (if not more so).
His books include Gardening With Grasses (1998) (with Michael King and Beth Chatto), Dream Plants for the Natural Garden (2000) and Planting the Natural Garden (2003) (both with Henk Gerritsen), Designing With Plants (1999) and Planting Design: Gardens in Time and Space (2005) (both with Noel Kingsbury).
His list of design projects includes the High Line (New York City, 2006), Battery Park (New York City, 2003), ABN Amro Bank (Netherlands, 2000), Hoogeland (Netherlands, 2001), the Lurie Garden, a gigantic green roof over the car park of Millennium Park (Chicago, 2003 - with Kathryn Gustafson) and Scampston Hall (England, 2002-2003). He is the designer of the interior garden of the 2011 Serpentine Gallery Pavilion in London, in collaboration with the Swiss architect Peter Zumthor.
His own garden, at Hummelo, near Arnhem in the Netherlands, makes reference to traditional Dutch gardens in its use of neatly clipped evergreen hedges.