Bonsai House

History and use

Built in 1887, Kew’s Bonsai House was originally used for displaying Alpine plants. Over the years it was enlarged and reconstructed. In 1981, when a new Alpine House opened, the glasshouse was relegated to growing campanulas and mossy saxifrages for the Alpine Nursery. Then, following construction of a new nursery in the 1990s, the conservatory was emptied and its rotting wooden structure replaced with a new aluminium frame. It now exhibits Kew’s growing bonsai collection.

Kew's bonsai collection

Bonsai are ornamental trees or shrubs that are grown in pots and pruned to present a miniature version of a mature tree. The word comes from the Japanese terms bon ‘tray’ and sai ‘planting’. Most of the plants in Kew’s collection were donated by Ruth Stafford-Jones in 2001. For 25 years she acquired bonsai trees and seeds while accompanying her husband on business trips to Japan. Subsequent gifts include two 85-year-old Chinese junipers (Juniperus chinensis). These are possibly the earliest surviving Bonsai imported to Britain.

Things to look out for

The ten bonsai looking their seasonal best are displayed at any one time. Because they are outdoor trees, they are frequently rotated to keep them in good health. Among the collection are a large Japanese maple and an aged needle juniper that were once owned by Kyuzo Murata, famed in the bonsai world for having saved the Japanese emperor’s treasured collection during the Second World War. Kew’s bonsai also include a wisteria which is only displayed when blooming in early May.

• Look for evergreens with unglazed pots, broadleaved trees in pots glazed in earthy tones or fruit trees in colourful pots.
• Keep your eyes level with the base of the trunk to view the bonsai like a mature tree.
• Imagine viewing a miniature landscape. The tree is on a hill of compost sloping down towards the edge of the pot.
• Bonsai have a front and back, with more foliage behind to create depth.
• The trees lean slightly forwards with branches that become smaller towards the top.
• A group of trees should have an odd number of trunks, all visible from the front and the side. Sometimes smaller trees are planted towards the back for perspective.

Behind the scenes

Bonsai require frequent watering. During the heat of summer, Kew’s bonsai specialist Richard Kernick checks and waters the collection up to three times daily. He re-pots around a quarter of the trees every spring; prunes in spring, summer and autumn; and wires branches in winter.

Kids’ mission

See if you can spot one of the following trees in the Bonsai House (they are not always on display but you have a good chance of seeing at least one of them on any given visit):

• Japanese maple (Acer palmatum)
• Chinese juniper (Juniperus chinensis)
• Hawthorn (Crataegus monogyna)
• Japanese cedar (Cryptomeria japonica)
• Beech (Fagus sylvatica)
• Larch (Larix decidua)
• Japanese black pine (Pinus thunbergii)

Once you have found one of the bonsai trees listed above, find a normal-sized tree of the same species in the Gardens. Have your photo taken beside each one so you can see the difference in size.