Form a rockery garden over a natural slope or hill in your property where you cannot plan a traditional garden. According to the Colorado State University Extension, the elements a rockery garden requires include good drainage and a slope. Use different sizes of the same type of rocks and a variety of plants, including creeping perennials and annuals, dwarf trees, bulbous plants and mini shrubs, to add varied colour and texture. Assess the sunlight and soil conditions of the area and plant accordingly.
The creeping variety of the evergreen juniper shrub or tree planted in gardens across the United States, creeping juniper (Juniperus horizontalis) is a rockery garden plant because it grows 6 to 10 inches tall and spreads branches horizontally. Depending on the cultivar, the plant features greenish-grey, greenish-blue or deep green foliage that turns deep plum in the winter. The drought-resistant variety prefers moist soils but grows equally well in dry areas as well. Plant it in soils that receive at least six hours of direct sunlight, as its branches grow thin and spindly when it gets too much shade.
A low-growing ground cover that grows between 5 to 10 inches tall, carpet bugle (Ajuga reptans), also called ajuga or bugleweed, features 2-inch-long, dark-green leaves and tiny blue to purple-blue flowers that bloom in spring and summer. The perennial propagates by above-ground runners and spreads quickly to cover an area with its foliage. Extensively used in rockery gardens and under larger shrubs, carpet bugle prefers moist, shaded soils and resists drought conditions.
Sea pink, or sea thrift, features tufts of grasslike foliage that grow between 5 to 12 inches tall and produce pink, white or purple dome-shaped flowers at the tips every summer. According to the University of Vermont Extension, the plant is suitable for rockery gardens, containers and edging borders. Although it withstands dry conditions and infertile soils, the plant thrives in well-drained, moist soils that receive full sunlight.
Related to the mustard, basket-of-gold is a mountain flower native to southern and Central Europe. Its dwarf variety, suitable for rockery gardens and as an attractive ground cover, is alyssum (Aurina saxatilis). The plant features greenish-grey foliage and thick clusters of yellow flowers that grow 6 inches tall and up to 12 inches wide. Alyssum looks beautiful when allowed to cascade down rocks because it covers the area with its yellow blooms. It prefers full sunlight to light shade. Plant seeds two weeks before the last frost or in early fall.