Two practices exemplify and highlight the problems we have in defining ecological planting design. Piet Oudolf in the Netherlands and Oehme/van Sweden in the USA have achieved high public-profiles for their innovative work. Both practices are noted for their extensive research of plant material and its use. They have both developed a distinctive aesthetic that is closely bound up with the visual qualities of the plants they use, which, in many cases, are species that have not been widely used in garden or landscape design previously, particularly ornamental grasses. Whether seeking such attention or not, their work has been seized upon by commentators anxious to promote a ‘natural’ approach to landscape design.
Oudolf’s work has been very favourably written up in Britain by writers for consumer magazines and garden books, who confuse him with other, chiefly German, practioners, and hail him as a leading light of a naturalistic style (Brooks 1998; Buchan 2000). Practicing in the Netherlands, the UK and more recently in the US, his work dramatically counterposes a highly individualistic interpretation of the formal treatment of woody plant material with a floristically rich assemblage of ornamental forbs and grasses. An architectural and very contemporary use of clipped evergreens recalls the mentor of his youth, Mien Ruys, but it was his discovery of the dramatic power of perennials and grasses that led him to develop the style that established his reputation. ‘My biggest inspiration is nature, not to copy it but to get the emotion,’ he says, ‘what I try to do is to create an image of nature’ (Oudolf 1998). Much of the innovatory appearance of Oudolf’s perennial plantings has been due to his use of grass species and of forbs that have traditionally been eschewed by horticulture, in particular the Apiaceae and genera such as Sanguisorba. A great many of the taxa used are genetically identical to wild stock, and of those that are not, many are cultivar selections of this wild stock, and of the hybrids used, nearly all maintain the proportions and, therefore, the aesthetic qualities of wild plants.
In addition to using plants to evoke wild places, Oudolf seeks to evoke nature by confronting his public with an aesthetic philosophy that celebrates the beauty of plants at all stages of their lifecycles. Setting himself firmly against the conventional horticultural practice of cutting back herbaceous vegetation in the autumn, Oudolf leaves his standing until the spring, waxing lyrical about the shades and shapes of dying leaves. He once said, only half-jokingly, ‘a plant is only worth growing if it looks good when it is dead’ (Oudolf 1994).
However, Oudolf’s work pays little attention to ecological criteria in selecting plants, which instead are put together using a subtle and innovative set of aesthetic criteria, which stresses plant structure and visual texture. Unlike the German Lebensbereich practioners, Oudolf does not group plants by habitat, or use ecological criteria in selecting plants any more than the vast majority of garden design practitioners (Oudolf and Kingsbury 1999:73). The design of his private garden features the placing of individuals of particular taxa in such a way as to evoke the intermingling of wild plants, although they are no more dynamic than that of many other garden designers who work with an informal approach—allowing a limited amount of self-seeding. His public work (e. g. Drompark at Enkoping, Sweden, and the Pensthorpe Waterfowl Trust at Fakenham, Norfolk) uses irregular-shaped blocks of herbaceous planting, each one characteristically using multiple individuals of a single taxon. The effect is thus profoundly different to that of natural vegetation.
In the US, the work of Wolfgang Oehme and James van Sweden has served to radically transform perceptions of the relationship between plants and landscape, particularly in public spaces. At first glance their work might seem to be profoundly ‘unecological’, featuring, as much of it does, large swathes of monocultural blocks of a limited number of taxa, especially in public landscapes (Ktihn 1999). Their planting style has to work within some severe practical constraints (e. g. deer predation and a poorly developed horticultural tradition), and the cultural and ideological constraints of a society where anything other than mown grass is still seen by many as ‘weedy’. Van Sweden himself once said, when looking at a planting of the author’s in England, that ‘the American public aren’t ready for this yet’ (Van Sweden 1998a). Like Oudolf, Van Sweden aims to evoke the emotion of wild landscapes, particularly the prairie plants he knew in his youth (Van Sweden 1998b). Massed grasses and tall perennials waving in the breeze are indeed very evocative, and have been taken to heart by the partnership’s increasing band of admirers. However, those of a more ecological bent have criticised them for using non-natives., such as potentially invasive miscanthus grasses, and for producing work of a formulaic nature (Darke quoted by Burrell (2000)). Another prominent promoter of native plants (name withheld) told the author that if he proposed to include their work in this study he should ‘go to Walt Disney World’.
Such criticisms, however, ignore the continuing evolution of their style. Sheila Brady a partner in the practice, describes how they are ‘moving much more towards interplanting whereas before we had masses of one species’ (Brady 2001). Eric Groft, another partner in the practice, is emphatic in describing their work as ‘natural’, in that it aims to ‘let plants be plants…clipped hedges for example, are not part of our vocabulary’. What is more, he sees their work as ‘ecological’, as ‘plants have to be well-chosen for their environment’ (Groft 2001). In some of the larger private plantings that the practice has worked on over the last 10 years, native plant community meadows have been used in situations where ‘anything like our normal planting becomes cost-prohibitive’ (Groft 2001).
The ‘classic’ work of Van Sweden and Oudolf is clearly not ecological in our understanding of the term, as they are not in any sense self-sustaining plant communities, plant selection is only loosely tied to ecological criteria and plant groupings are built around monocultural blocks of varying sizes. However, they successfully evoke ‘nature’ to many observers, and have played major roles in promoting the broad concept of naturalistic design. What is more, their undeniable creative skill, originality, professional boldness and success are an inspiration to all in the profession.
The larger-scale Oehme Van Sweden work is one that clearly has its roots in a 1950s German parks style, with its sculptural, almost Burle Marxian, flowing mass of perennials. Arguably, we have now come full circle, with German designer Petra Pelz working with perennials in public spaces in a bold style that is inspired by the two Americans, with little obvious reference to an ecological style (Ktihn 2001). Pelz, like many designers, is acutely aware of the problems of maintaining plantings in public spaces, and finds from her experience or working in Magdeburg, that simple, very structural plantings are easier to maintain than more finely-structured ones. In seeking to
develop planting combinations that form weed-suppressing carpets, her work is also arguably a simplified version of the Lebensbereich style (Pelz 2001).