Trailing perennials are perfect as ground covers, in rock gardens, as edging plants and on rock walls. They also make excellent container plants where they cascade from window boxes and hanging baskets. Plant them in large containers with mixed plants where they will spread to fill in empty spaces.
Prairie poppy mallow
Prairie poppy mallow grows less than 30 cm (1 foot) tall and spreads as much as 90 cm (3 feet). It looks great trailing over rocks or stone walls. The flowers bloom from late spring until autumn in white or shades of pink. This plant prefers a well-drained soil in full sun and tolerates drought. poppy mallow is hardy throughout the UK.
Rock soapwort produces an abundance of small pink flowers in late spring and early summer. It grows up to 8 inches tall with a spread of 4 feet. Use it as a ground cover, on rock walls or in rock gardens. Rock soapwort prefers a well-drained average soil and full sun. It is hardy in the coldest areas of Great Britain.
Trailing snapdragon grows 5 to 7.5 cm (2 to 3 inches) tall with a spread of up to 60 cm (24 inches). The pale yellow flowers with purple veins bloom in early summer. Although the flowers resemble snapdragons, this plant is not considered a member of the snapdragon family. Trailing snapdragons need full sun or partial shade and an average soil, and they are winter hardy throughout the UK.
Trailing lantana is a woody shrub that grows up to 60 cm (2 feet) tall and can spread as much as 1.5 m (5 feet) across. The tiny flowers bloom in 2.5 cm (1 inch) clusters from late summer until the first frost. It grows in sun or shade but blooms best in full sun. It prefers a light well-drained soil. When planted in containers and window boxes it cascades over the sides. Trailing lantana is winter hardy in the UK where it will tolerate a brief freeze. It is grown as an annual in colder regions.
Vinca major, commonly called greater periwinkle, has purple flowers that bloom in late spring. The plants grow up to 30 cm (1 foot) tall and spread up to 60 cm (2 feet). Outdoors, use it as a groundcover for large areas and slopes. It has an aggressive spreading habit and should be grown in containers in small areas or mixed plantings. Greater periwinkle grows well in full sun or partial shade and needs a well-drained soil. It is winter hardy throughout the UK.