The Sir Harold Hillier Gardens is an arboretum comprising 72 hectares (180 acres) accommodating over 42,000 trees and shrubs in about 12,000 taxa, notably a collection of oaks, camellia, magnolia and rhododendron. The Gardens are located northeast of the town of Romsey in Hampshire, England, and were formerly known simply as the Hillier Arboretum, founded by nurseryman Harold Hillier in June 1953 when he acquired Jermyn's House and its grounds. The arboretum was given to Hampshire County Council in 1977 to be managed as a charitable trust. Sir Harold Hillier was knighted in 1983, just two years before his death at age 80 in 1985. The Gardens were listed as Grade II on the National Register of Historic Parks and Gardens in 1997. Organisation Run as a registered charity, the Gardens are continually developed to further Sir Harold’s philosophy of horticulture, conservation, education and recreation. The president of the trust is the Duchess of Cornwall and the patrons are Lord Sainsbury and Roy Lancaster, who was the first curator. A team of 18 experienced horticulturalists and arborists look after the collection alongside students and a team of 200 volunteers. Collections Sir Harold Hillier Gardens has one of the largest collections of hardy trees and shrubs in the world and is famous for its collection of rare plants. National Plant Collection It is home to 14 National Plant Collections including: Carpinus (hornbeam) Cercidiphyllum (katsura trees) Cornus (dogwoods) Corylus (hazels) Cotoneaster Hamamelis (witch hazels) Hillier Plants Hypericum Ligustrum (privets) Lithocarpus (stone/tanbark oak) Metasequoia (dawn redwoods) Photinia (christmas berry) Pinus (pines) Quercus (oaks) Champion Trees Sir Harold Hillier Gardens has the most comprehensive collection of Champion Trees in Britain and Ireland with 611 trees that are considered to be the largest, finest, or most rare of their species, as recorded by the Tree Register of the British Isles in 2020. The collection includes Metasequoia glyptostroboides, from the original batch of seed received by the Arnold Arboretum from China and distributed in 1948, its first introduction to the West. The young shoot is the emblem of the Gardens. Rare Plants Sir Harold Hillier Gardens is renowned for its collections of rare plants. Gems include: Magnolia macrophylla subsp. dealbata, with leaves up to 3ft long and large, fragrant, white flowers. Calycanthus x raulstonii ‘Hartlage Wine’ is a magnolia relative, a spice bush hybrid with large red flowers, a real exotic looking beauty. Puya alpestris, flowering