Nick Hawkins / Red trillium (Trillium erectum), photographed on white background, New Brunswick, Canada, May.

Doug Wechsler / Red Trillum (Trillium erectum) Fairmount Park, Wissahickon Creek, Philadelphia, Pennsylvania, USA, May.

Loic Poidevin / Purple trillium (Trillium erectum) Jacques Cartier Park, Quebec, Canada, May

Loic Poidevin / Purple trillium (Trillium erectum) Jacques Cartier Park, Quebec, Canada, May

Jerry Monkman / Red Trillium {Trillium erectum} flower, Mt. Passaconoway, New Hampshire, USA

Jaymi Heimbuch / Purple Trillium (Trillium erectum) flowering, Butano State Park, California