Rocks have always played a central role in the gardens of China and Japan, but the Western rock garden is a fairly recent development. Before the Romantic Movement of the late eighteenth century, there was very little interest in alpine plants. Mountains were seen as barriers to cross. Shepherds and hunters explored them, but most people saw mountains as dangerous places, to be avoided whenever possible. The romantics of the late eighteenth century fell in love with the wild beauty of the Alps, and Switzerland developed a thriving tourist industry. This was also the period when rockeries first became popular in European gardens.
There is a tendency for English speaking people to focus too much on British gardens. The British dominated the gardening world from the middle of the eighteenth century to the early nineteenth century. The British are still a major force in the gardening world; many of the top "gardening gurus" are British. It is easy to ignore the fact that some of the most important romantic gardens were created in Germany. The Germans created some very dramatic gardens which featured water cascading among huge stones. The late eighteenth British rockery tended to be on a more modest scale and was often a display of various kinds of rocks rather than a garden. Many alpine plants were introduced to cultivation during the nineteenth century and people began to plant them among rocks. The first rock gardens were rather unsophisticated, there was little attempt to arrange the rocks in a naturalistic manner. By the late nineteenth century, designers were arranging rocks to look like natural outcroppings. The fashion for rock gardens reached its peak during the 1920s and they have remained popular, especially where large rocks are used to retain banks.
Most, but not all dwarf rhododendrons are true alpines which grow in large colonies above the treeline. The word "dwarf" is a bit deceptive. Some dwarf rhododendrons form mats of foliage 2 inches (5cm) tall; most grow from one to four feet (30cm - 1.20 m) tall. It isn't unusual for dwarf rhododendrons to reach 6 feet (2m) in height. Rhododendron minus can reach 30 feet (10m) in the wild, but in cultivation it rarely tops 6 feet (2m). This is also one of the dwarfs which is not a true alpine; it is native to forests on the mountains and plains of the Southeastern United States, from Carolina to Alabama.
