Lobelia erinus

Lobelia erinus (edging lobelia, garden lobelia or trailing lobelia) is a species of Lobelia native to southern Africa, from Malawi and Namibia south to South Africa.

It is a prostrate or scrambling herbaceous perennial plant growing to 8–15 cm tall. The basal leaves are oval, 10 mm long and 4-8 mm broad, with a toothed margin; leaves higher on the stems are slender and sometimes untoothed. The flowers are blue to violet in wild plants, with a five-lobed corolla 8–20 mm across; they are produced in loose panicles. The fruit is a 5–8 mm capsule containing numerous small seeds.

Lobelia erinus is a very popular edging plant in gardens, especially for hanging baskets and window boxes. It has a particularly long flowering period, from mid spring to early autumn. It is perennial in subtropical climates, but often grown as an annual plant in colder areas. It is widely available in Spring as a young plant, but must be kept indoors until all danger of frost has passed.

Numerous cultivars have been selected, either with a bushy or a trailing habit, in a wide range of flower colours, including white, pink, red, pale to dark blue, and purple, often with a prominent white eye. Some of the better known cultivars include 'Blue Moon', 'Gracilis', 'Crystal Palace', 'Sapphire', 'Rosamund' and 'Riviera Rose'.