A Wilder Way - NYTimes.com See the interactive slide show Thousands of people walk New York's High Line every day - and for many of them it is not the views they have come to see, or the architecture, or each other, but the plants. The same could be said of Chicago's Lurie Garden in Millennium Park, where extensive drifts of flowering plants in permanently planted borders constantly draw in passers-by. These are examples of a new kind of urban planting, one with incredible public appeal - it is colorful but somehow also wild looking; there is plenty of seasonal change although the plantings are permanent, and they pull in urban wildlife too. Piet Oudolf, the Dutch designer who is responsible for the planting in both of these public projects, is also much in demand for planting private gardens, like this one in Nantucket, which showcases his horticultural philosophy. Once upon a time, planting in the city meant beds of brightly colored flowers that lasted for a few months before being dug up, disposed of and replaced with something else. It was all very labor intensive, resource-hungry and unsustainable. Oudolf's work is part of a movement that seeks to use long-lived, perennial plants, which need minimal management. In some projects, like Millennium Park, his first public commission in the United States, or at Battery Park in New York, volunteers get involved in basic maintenance work, providing an outlet for gardening energies and the desire to be close to nature. The city may have become our habitat, but we are increasingly learning how we can share it with other species - and the new perennial planting is central to how we are doing this. Oudolf's career as a garden and landscape designer has mirrored the growth of this new planting movement, of which he has been a pioneer. Born in the Netherlands in 1944, he has worked in garden design for most of his life. The tradition he came from balanced strong shapes, often formed from clipped evergreens, with rich planting. The flowering plants available, though, tended to emphasize color above all else and to be high maintenance. Oudolf found himself increasingly drawn toward plant varieties that kept the proportions and grace of their wild ancestors. In this he was not alone, for a whole generation of gardeners and garden designers in the Netherlands, Germany and Britain was looking at the visual possibilities of using wildflowers and nature-inspired plant combinations. In Germany, a number of publicly financed research bodies were applying plant ecology science to the management of public parks, while in Britain, a growing network of small specialist nurseries was steadily increasing the number of perennial plants in cultivation. Researchers in Britain also began to work on using seed mixtures to create extensive long-lived plantings - as was appreciated by visitors to last summer's spectacular Olympic Park in London. Oudolf began to use more and more "unconventional" plants in the gardens he made for clients. He was particularly drawn to plants with strong visual structures like grasses and members of the Queen Anne's lace family; he once said, only half-jokingly, that "a plant is only worth growing if it looks good when it's dead" - in other words, plants whose seedheads or winter foliage have strength and character are every bit as valuable as vibrant summer flowers. Finding commercial sources of these plants difficult, in 1982 he set up a small nursery to supply his design work. Run by his wife, Anja, the nursery developed a momentum of its own - soon British gardeners were finding their way across the Dutch countryside to visit and buy plants. Meanwhile in the United States, a similar process had begun with the work of Oehme van Sweden, who favored romantic drifts of ornamental grasses and blocks of perennial flowers rather than the trees, shrubs and lawn grass look that dominated American landscapes. Elsewhere in the United States, primarily in the upper Midwest, ecologists had begun to promote native wildflowers as an alternative to the conventional lawn. The idea of the garden was becoming steadily wilder. For large public projects, Oudolf collaborates with landscape architects, so that he can concentrate on the planting. In Chicago, he worked with Gustafson Guthrie Nichol and the set designer Robert Israel on the Lurie Garden: five acres of public garden above a parking garage. Small groups of perennials and grasses, over half of them Midwest natives, are intermingled on gently rolling ground. It is clearly a garden, but looser and less controlled than most of us had seen before. The garden created a huge amount of public interest, with people strolling through and bombarding garden staff with questions. The New York High Line was a collaboration between Oudolf and the landscape architects James Corner Field Operations (who also did the master plan for the Nantucket garden). Wilder still than the Lurie Garden, the High Line again used a very high proportion of regionally native plants. Oudolf devised a method of precisely planning the distribution of the plants so that it looks almost as if nature had put them there. Wild grasses tend to form a matrix in areas, with flowering perennials interspersed between them. Small trees and shrubs are used in other areas, with an underlayer of the kind of plants that are very similar to those that might be found beneath trees in natural woodlands. For many a city dweller, this is about as close to nature as they will ever get. For urban bees, butterflies and birds, this is nature. The garden on Nantucket also uses drifts of mostly native American grasses to create the effect of wild grassland, but on a far more expansive scale; visually they tend to complement and even highlight the flowering elements as well as have their own intrinsic beauty - one especially appropriate to the open coastal landscape of the island. The evocation of natural habitats may look carefree and unplanned, but this is the result of many years of research, and the latest stage in a continuing and collaborative journey.