Sharing know-how about UK gardening

July colour

Our visit was at just the right time to see the astilbes and Japanese irises at their best. Dr Smart assembled national collections of both of these Oriental plants here and planted them in spectacular groups in different parts of the garden.

The feathery plumes of red, pink, purple and white astilbes light up the borders surrounding the lakes and add to the party-frock colours of the broad bog garden.

Altogether there are about 120 cultivars of various species grown here. Most need the moist conditions provided by a bog garden or a well-watered and mulched soil, although Astilbe simplicifolia and A. chinensis can tolerate drier conditions. Fortunately these are some of the smaller astilbes, growing only 18-30in high, so are suitable for small gardens - whatever the size of garden, for best results, astilbes should be planted shallowly, and dug up and divided every three to four years.