Holden Arboretum

The Holden Arboretum, in Kirtland, Ohio, USA, is one of the largest arboretums and botanical gardens in the United States, with over 3,600 acres (1 456 ha), 600 acres (243 ha) of which are devoted to collections and gardens. Diverse natural areas and ecologically sensitive habitats make up the rest of the holdings. The Arboretum's collection includes 9,400 different kinds of woody plants, representing 79 plant families.

Specializing in the woody plants that can be grown in the climate of Northern Ohio, Holden has a number of specimens obtained during wilderness collection trips, particularly to China and Korea near the 40th parallel, areas with a similar climate to Northeast Ohio. Holden is home to two National Natural Landmarks, accessed by guided hikes, and is Midwest representative for The Center for Plant Conservation. Special gardens include the Myrtle S. Holden Wildflower Garden, the Helen S. Layer Rhododendron Garden, and the Arlene and Arthur Holden Jr. Butterfly Garden. The Holden Arboretum also features extensive Crabapple, Lilac, Viburnum and Conifer Collections.