Highgrove Gardens, Gardening at Highgrove

‘Gardening at Highgrove’, a fascinating and informative talk, was given by Head Gardener David Howard of Highgrove House, on the 10th April 2005 in the Vaynol Hall, near Bangor North Wales. David Howard outlined the development of the gardens over the past 25 years. It is now a garden which incorporates many styles and every aspect is managed with an organic ethos - the plant pots used, the composting, even the string, originate from organic sources. Very few items are brought in - raffia, hemp, sisal come from abroad - but they again are organically grown and deliberately purchased from communities which will directly benefit. For the general management of the gardens and the estate, the only material brought in is sharp sand. This is inert and therefore acceptable in an organic regime. No peat is used and everything that can be is recycled. Plant material usually takes twelve weeks to be composted and is then reused as compost or mulch. David gave a guided ‘walk’ through the estate using transparencies to illustrate the various gardens within the larger garden, beginning with the wildflower meadow ox-eye daises in its famous ‘white phase’ and with its more recent additions of blue Cammasia which gave added interest to the setting. The Tulip Garden, which is equally renowned, has had its flowering period extended from two and a half weeks to six weeks with the planting of 9,000 bulbs and the inclusion of sorrel. These meadows are managed by cutting in mid-July, either for hay or silage, depending on their quality, and are both used organically on the estate. The Cottage Garden was created six years ago by Rosemary Verey and has a wide ranging assemblage of more unusual plants, including Stipa gigantea and Aconitum species giving colour throughout the summer.
The Thyme Walk has had to be totally reconstructed as drainage was inadequate and this had resulted, over a number of years, in woody thymes. This area, as a consequence, had become very untidy. The area was meant to be maintenance free but unfortunately did involve considerably more work than one imagined. Two tons of pea gravel and twenty tons of ordinary gravel overlie Mypex membrane and this has created the right habitat for the ‘new’ Thyme Walk. This new habitat is now well drained, relatively maintenance free and as it was originally envisaged. The Lily Pool Garden (Mediterranean Garden) is one of the hottest parts of Highgrove where roses with mixed borders do well. On the south side of Highgrove, a sundial garden was designed to be truly unique. The result is a Black and White Garden. White lupins have been planted against black aquilegias and the black foliage of the dahlia ‘Bishop of Llandaff’ is stunning where the flower buds are continuously removed to stop the brilliant red flowers. The Arboretum with its snowdrops is now a feature in Spring and a collection of unusual specimen trees, many from nearby Westonbirt Arboretum, give spectacular autumn colour. This area has been developed over the past twelve years – a much shorter period of time than one would imagine from its appearance. Close by is the Azalea Walk which typically is at its best during Chelsea week. To add extra interest, purple clematis has been used to twine through the azalea branches.
In the Woodland Garden, a stumpery has been developed from over two hundred huge oak and sweet chestnut stumps, which do not rot easily due to their high tannin content. Surprisingly only a few genera planted here – Ruscus, ferns, Euphorbias, and hellebores - foxgloves, as natives, are allowed to seed themselves naturally. It is also home to the National Collection of Hostas and of Fagus and there are plans to have other National Collections in the near future. These will act as genetic resources for horticulture in general. The Wall of Gifts, a collection of students’ work that was to thrown away from a local college, together with large quantities of local church sandstone that would also have been discarded, forms an interesting feature here and represents the emphasis on recycling prevalent throughout the gardens. The Fern Pyramid provides an interesting focal point. Made of welded mesh, its centre is filled with a mixture of loam and compost on a yearly basis. Another focal point, and one very popular with tours, is the new walled area with an Islamic theme at the eastern end of the garden. However it has been very difficult to maintain - many of the plants are frost sensitive and have to be put into glasshouses over winter for protection. Furthermore, the Spanish tiles used for the mosaics crack with frost and cause even more problems of replacement. As in the rest of the garden, ceramic pots feature extensively. In fact in almost every garden, pots of all descriptions and sizes have been used to great effect.
The sewage system, although not popular with visitors, is an important, integral part of Highgrove and deals with all its effluent. All the sewage is treated using beds of Phragmites and willow and the resulting water, stripped of nitrates and phosphates, is of very high quality and soaks away into the nearby waterway. There are spin-offs in the creation of a very rich, biodiverse site which has abundant wildlife and crops of willow. These are used to make baskets which are sold to the public along with other produce such as fruit and vegetables. These are, of course, all organic.
The extended garden outside the twenty-five acres of what could be loosely termed the main garden includes the surrounding parkland. Again the same ethos of organic management and increasing biodiversity is applied. Here many rare breeds are maintained as a valuable source of genetic material. This is an important resource for agriculture.
In summary, Highgrove is a garden with many gardens within. It is unique in that not only is it a rich source of ideas which any individual gardener can apply, it also provides professional gardeners with a resource of scientific and educational materials. It is not a botanic garden; in one sense, it is a very private, personal garden and is a reflection of its owner. In another sense, it is a living, real, permanent ‘Chelsea Flower Show’ and something extra that this show can never have. In the Chelsea Show each garden is just a snapshot in time sand is totally artificial. In Highgrove each garden is real, permanent and evolving in time. More important than everything else, the whole system, the ‘Garden’, gardens and parkland, is as organic as anything can practically be and as an attempt to follow natures’ laws, it is a place to treasure for generations to come.