Family: Ranunculaceae

This large genus of 400 species of annuals and perennials is widely grown throughout the world. The leaves are variable, some entire, some deeply divided, while the flowers range in colour from white to yellows and reds. Cultivated varieties include pinks and oranges as well. One species, R. asiaticus, and its cultivars are popular bedding plants and make excellent cut flowers. Ranunculus are poisonous if eaten and are rarely, if ever, grazed by stock.

Species

R. acris, meadow buttercup, zone 5, from Great Britain and Europe, is a hairy plant with very long flower stems which can be up to 90 cm (36 in) and on which balance the lovely, golden, cup-shaped flowers.

R. asiaticus, Asiatic ranunculus or Persian buttercup, zone 9, from the Mediterranean region and south-west Asia, is parent to many beautiful hybrids and cultivars. It is a tuberous perennial, grown as an annual, with segmented leaves and erect flower stalks. Masses of large, multi-petalled, single or double flowers appear in late spring and early summer on 35 cm (14 in) stems. These beautiful blooms come in many colours, from yellow, orange and red to pink and white.

R. collinus, zone 8, is a mat-forming Australian, alpine species, with wedge-shaped leaves and almost stalkless, yellow flowers.

R. lappaceus, common or native buttercup, zone 9, originates from both Australia and New Zealand, where it is often found in damp or marshy places. This fibrous-rooted perennial has deeply lobed leaves and shining, yellow, cup-shaped flowers.

R. rivularis, zone 9, found in most states of Australia, is a water-loving, mat-forming perennial, growing to around 1 m (3 ft) across, with shining, yellow flowers in summer.

Cultivation

R. asiaticus and its cultivars require deep, well-drained soil, enriched with plenty of organic matter, and a sunny position, sheltered from strong wind. If necessary, about 100 g (3½ oz) of complete fertilizer to each square metre (yard) of soil should be dug in some weeks before planting. Propagate from seed sown in summer and transplant seedlings when about 5 cm (2 in) high, setting them 15-20 cm (6-8 in) apart. Flowering should occur in late spring to early summer. Alternatively, commercially grown tubers are available in mixed or separate colours, usually producing more robust plants. Set tubers, claws down, in a bed, 15-20 cm (6-8 in) apart and about 4-5 cm (about 2 in) deep, between late summer and early autumn. Young plants need weekly watering once growth begins and may be given weak liquid fertilizer when the flower buds appear. The tubers are lifted when the foliage has died down and are stored in a cool, dry, airy place until the following autumn. Flowers may be poorer in the second or third season. In frost-prone climates, Asiatic ranunculus, which is half-hardy, can be grown in pots in a cool greenhouse or conservatory. Most of the Australasian species are from alpine regions and are suitable for cultivation as rockery plants. Most are water loving and are especially suitable for cool-climate cultivation. Propagate from cuttings placed in a sharp sand and peat mix of 2:1. Alternatively, the clumps can be divided in spring or autumn. Many of these species make good groundcover plants for damp and shady spots.

Climate

There are species suited to various climatic zones.