The nursery, initially a wholesale enterprise, was founded in 1958 with the appointment of James Duncan as Director of Gardening.

Immediately to the south is an 80 m herbaceous border; running parallel with it is a clematis and fruit tree archway, flanked by beds of Buddleja cultivars.

The gardens were formed by accident; in 1870, Alfred and Arthur East, the owners of Longstock House, had gravel dredged from the banks of the River Test to construct a private road to their property, creating the lake in the process.

After the Easts sold the property in 1914, Reginald Beddington, son of the new owner, elected to make an aesthetic feature of the lake.

The arboretum was begun in 1869, and now comprises 28 hectares of mature trees including a pinetum with many exotic conifers.