Hidden treasures

Colby Woodland Garden, Pembrokeshire

The secluded woodland setting of Colby hosts one of the finest collections of rhododendrons and azaleas in Wales.

© NTPL / Andrew Butler

Colby never fails to impress. It is noted for its spring bluebells, its summer hydrangeas, herbaceous borders, specimen trees and shrubs and its spectacular autumn colour. The walled garden, Gothic-style gazebo and water feature add structural interest.

The Courts, Wiltshire

From 1920 Lady Cecilie Goff, influenced by Gertrude Jekyll and Lawrence Johnston, created delightfully vibrant formal gardens divided by yew hedges, shrub borders and raised terraces.

© NTPL / Stephen Robson

The Hidcote-style garden is packed with many interesting plants and imaginative colour schemes. Features include a conservatory, lily pond, mixed borders and pleached limes. The arboretum contains fine specimen trees under-planted with spring bulbs

Greys Court, Oxfordshire

At Greys Court, the remains of the 14th-century medieval manor fortifications form a series of charming walled gardens. Within the walls, the white garden features magnolias, lilies and peonies.

© NTPL / Stephen Robson

The rose garden, planted with old-fashioned roses, leads to a circular walled garden enclosing ancient wistarias. The wall of the medieval tithe barn partly encloses a walk of Japanese cherry trees. The kitchen garden is planted with espaliered fruit and vegetables. Beyond the kitchen garden is the Archbishop's Maze.

Trengwainton Garden, Cornwall

Trengwainton, which in Cornish means 'house of spring', is a plantsman's paradise. The favourable climate allows many rare plants to be grown unprotected against frost. The unusual walled garden, constructed in 1820 for early vegetable crops, now houses a wonderful collection of trees and shrubs.

© NTPL / Andrea Jones

Some rhododendrons flowered at Trengwainton for the first time in the UK after being collected by the renowned plant hunter Frank Kingdon-Ward. As well as its stunning collections of rhododendrons, camellias and magnolias, the garden has a stream running almost its entire length, with plantings of astilbe, primula and New Zealand tree ferns.

A walk to the top of the garden gives magnificent views over Mount's Bay

Washington Old Hall, Tyne & Wear

The garden at this modest 17th-century manor house, the ancestral home of George Washington, first President of the United States, is newly created.

© National Trust

It is filled with English flowers and herbs of the 17th century, some of which are now rare. The parterre is also in formal Jacobean style. Other features include a walled border with buttresses, beech 'elbow' hedging, a formal pathed lawn with a wildflower mead and formal hedging.