Between 1819 and 1835, Lord Sidmouth, Deputy Ranger, established several new plantations and enclosures, including Sidmouth Wood and the ornamental Isabella Plantation, both of which are fenced to keep the deer out. After World War II the existing woodland at the Isabella Plantation was transformed into a stunning woodland garden, which is organically run, resulting in a rich flora and fauna.
Opened to the public in 1953, the Isabella Plantation is now a major visitor attraction in its own right. In October 2012 it was reported that about 40% of the Isabella Plantation is covered with Rhododendron ponticum, a non-native and invasive variety of rhododendron introduced by the Victorians, and that this will be removed over the next five years. The garden is also a good place to see various species of birds, such as redpoll or wood pecker, among others.
Being an ornamental woodland garden, the Isabella Plantation is full of exotic plants that are arranged to be interesting all year round. In the garden there are 15 known varieties of deciduous azalea and the collection of 50 Kurume azaelas, as well as Japanese irises and day lilies. The garden also has 50 species of rhododendron and 120 hybrids.