Rockeries are constructed as natural-looking rocky outcrops, ideally on a slope in full sun. They work particularly well alongside ponds, water features or next to walls and can be given extra height and contours using railway sleepers if your garden is naturally flat. The best rockery plants are alpines - low, slow-growing varieties that are happy in dry areas. Alpines require a well-drained soil and open position away from trees. A layer of grit on the surface helps drainage and deters slugs.
Aubretias such as Aubretia Red Cascade have a neat, compact habit with attractive yellow-centred flowers which look particularly attractive against the rocky backdrop. Sedums are pretty groundcover plants with tight mounds of foliage and spring-summer flowers; try Sedum Purple Carpet or Sedum Brilliant. Dwarf conifers such as Chamaecyparis Boulevard provide colour, texture, year-round interest and good weed cover, whilst many heather plants boast vibrant foliage and attractive flower spikes. Finally, use wispy or vibrant grasses such as Imperata Red Baron or Helictotrichon to add colour and texture.