Cascading rock garden plants thrive where others cannot. An ugly retaining wall, an unsightly slope or a steep hillside can be turned into a vibrant focal point of dramatic colour and eye-catching appeal by establishing perennial plants to cascade and cover unattractive areas in the landscape.
Choose perennial plants that are low growing and clumping. Plants that cascade to create a draping effect in the rock garden include Basket of Gold, ivy, alyssum and rock cress, Rockfoil and Creeping Broom. Irish Moss, Lewisia, Moss Pink and Ice Plants are well adapted to the rock garden, filling in bare spots and growing in cascading mounds to add dramatic colour and scent to the garden. Mat Daisy and lemon thyme quickly fill in bare spots in the rock garden.
Provide good drainage. Plants suitable for rock gardens require well-drained soil. Mix organic matter into clay soils to improve texture and drainage.
Plant a wide variety of species. Repeat some plants several times to help make the garden look natural.
Do not over-plant. Rock garden plants need space to spread to form cascading clumps.
Water frequently. Rock gardens with correct drainage dry out quickly in the summer sun. To encourage growth, water twice weekly.
Ground-cover sedum is a low creeping plant, ideal for along walls or in rock gardens.