Wildlife-Friendly Gardening at Wisley Talk by COLIN CROSBIE, 9th February 2005

When the Royal Horticultural Society took over the garden at Wisley in 1903, like every other gardener its staff would have relied heavily on the use of pesticides and fertilisers, regardless of the (then unappreciated) detrimental effects on our native flora and fauna.  Things are very different today, however - 'gardening with wildlife' being very much the motto of the present-day management.

This was the theme of the highly entertaining and enlightening talk by COLIN CROSBIE, Superintendent of Woody Ornamentals at Wisley, who pointed out that, although the garden is not yet completely organic, the use of chemicals is now the last option the gardeners turn to.  Instead, for example, a direct line to Met Office reports on air temperature and humidity enable staff to predict when aphid attack is likely and a highly specific aphicide can be sprayed on susceptible plants, instead of repeated spraying throughout the season.  Also soils are regularly tested to ensure that only as much fertiliser as needed is applied, thus avoiding waste and potential run-off that could pollute water courses.

The rest of Colin's talk took the form of a 'walk around Wisley', illustrated by a host of colourful slides of the different areas of the garden and the wildlife that can be found there. In front of the (rather grand) laboratory building, for example, is a canal where a Kingfisher is a regular feature (until the visitors arrive, when it heads for the nearby River Wey).  The mixed borders, which provide a breathtaking show of colour from May through to September, also provide a rich supply of nectar and pollen for visiting insects - including night-flying moths - one of the most attractive to them being Verbena bonariensis.  The sedums are also excellent in this respect although Colin warned, for anyone thinking of planting these in their garden to attract wildlife, that some cultivars have sterile florets.  Another group of plants providing a useful food supply is the cone flowers (Echinacea and Rudbeckia spp.), whose huge seed heads are a magnet for birds such as tits and Goldcrests in the autumn. In the past these would have been removed in an effort to keep the borders spick and span, but now their value to wildlife is recognised - although apparently some visitors still complain that the borders look untidy as a consequence!

Similarly, elsewhere in the garden, dead wood is no longer cleared away but left in piles to rot, providing ideal habitat for a host of invertebrates.  Many of the living trees in the garden are riddled with woodpecker holes, providing homes not only for birds but also for bats and, while it is sometimes necessary to remove limbs and even whole trees for safety reasons, due care is taken to assess these for wildlife use before such work is done. Of course trees such as Rowans (Sorbus spp.) and Crab-Apples (Malus) also provide an important autumn food supply for birds such as Fieldfares and even Waxwings.

Set-aside areas, which would once simply have been mown when not in cultivation, are now sown with a wildflower mix. Interestingly, surveys have shown that while a greater variety of insects uses these areas at night, more use the borders mentioned above by day; thus the two complement each other, increasing the biodiversity of the area as a whole. Another important feature of the garden for wildlife is its network of ditches, streams and ponds (the name Wisley apparently means 'marshy area'): indeed, 90 years of recording have shown that insect diversity here is far greater than that on nearby Wisley Common.  Colin reminded us at this point that if you want to do just one thing for wildlife in your garden, you should build a pond!

This is just a small selection of the delights to be found at Wisley, so if you haven't been there lately do go - and remember, there is a lot more for the keen naturalist to experience than just the flowers.  More information can be found at http://www.rhs.org.uk/WhatsOn/gardens/Wisley/index.asp.

LYNN WHITFIELD