New climatic conditions make appropriate green spaces necessary: extreme temperatures, lengthening and shortening growing seasons, and less predictable rainfall patterns are indeed becoming real challenges in landscape design.
Its origins date back to the 1960s when the first movements against the intensive use of lawns emerged in the United States. A defining element of the garden idea such as the lawn was thus challenged for its excessive need for water, giving way to the concept of xeriscaping, or xeros, dry, + landscaping. A landscape, therefore, with little need for water and easy maintenance.
Even in Europe, particularly in England, similar needs are beginning to arise since the 1990s. Not all of England is as green and rainy as we imagine it to be. The countryside southeast of London, for example, is ill-suited to accommodate the botanical imagery commonly associated with the romantic borders of English tradition. From this realization arose in some quarters the need to rethink gardens in a more contemporary key, with the help of plants chosen according to where they are to be planted and not forced to have to be lush in climatic conditions that do not match their needs. After years of studying plants in their natural environments, British gardener Beth Chatto published the book 'The Dry Garden' in 1978, which was highly praised in the UK but criticized abroad: how can one talk about a drought garden in humid Britain? Steering clear of any ideological stance, Beth went on to prove that moderate human intervention can help an environment perform at its best, as long as its inherent peculiarities are respected.
The essences used for the Dry Garden are drought-resistant plants that can grow in areas with extreme conditions.
As is evident from observation of Köppen's Climate Classification, the botanical world that characterizes The Dry Garden consists of predominantly Mediterranean essences, which thrive in the two types of "dry" climate: the Mediterranean and the steppe climate.
The former is found in the Mediterranean basin, parts of California, and southern Australia. Botanically it consists of a wide range of essences in different shades of greens and grays, leaves of multiple textures, densities, and ways of reflecting light, colorful blooms in spring and summer, many aromatic plants, and many evergreens.
The second is found in the far southeast of the Iberian Peninsula, Morocco, the southern coast of California, and some inland areas of Australia. Here perennials, grasses, and bulbs grow luxuriantly with high drought resistance. They are less showy plants, but with spectacular spring blooms.
Regarding the type of soil, it is important to create a draining system without water stagnation.
During the first year after planting, irrigations will be more frequent, until the plant, as it grows, has achieved greater autonomy. During the very first years after planting, irrigations should be sparse and based on large amounts of water, as if to simulate summer downpours. In this way, water can slowly seep into the deeper layers of the soil, where the plant's roots will tend to seek it out. The purpose is to 'educate' the plant to receive water infrequently and to strengthen itself to survive almost self-sufficiently when watering drops further. Once the plants are well established, they will be totally self-sufficient.
The recommended time for planting plants is generally autumn: this choice allows them to develop deep roots over the winter, taking advantage of seasonal rains to secure the water resources they need.
If planted in the fall, by summer they will have had a chance to acclimate and develop a good root system, ready to seek moisture in the deep layers of soil.
On surfaces, the use of mulch can be useful to reduce evaporation and controlling weed vegetation. It can consist of organic material (compost, hazelnut shells, bark, etc.), which also offers the advantage of providing organic matter, or inorganic material (vulcanite, gravel, etc.).
Plants suitable for a dry garden include trees, tall and low shrubs, many aromatic plants, climbers, bulbs for all seasons, many herbaceous perennials, and good alternatives to lawns. There are thousands of endemic plants from various areas of the world with similar Mediterranean climates that have adapted to dry summer conditions. Beyond the bulbs and herbaceous perennials that disappear in winter to start up again with spring, most Mediterranean plants withstand summer drought because their major growing period is during the fall, winter, and spring when they can rely on periodic rains. Many have leathery, glossy, hairy, silvery leaves that help limit water evaporation. Color variety and foliage texture give many Mediterranean plants an interesting appearance even when not in bloom.
A research by: Ana Hebborn, Marianna Merisi