This very large genus comprises about 250 species of widely different habit and appearance, but R. asiaticus and R. repens pleniflorus are the species most commonly grown in gardens.Ranunculus asiaticus
Native to Asia Minor. Tuberous-rooted plant 1 1/2 to 2 ft. tall and wide, with fresh green, almost fern-like leaves. Blooms profusely in spring, when each flowering stalk bears one to four 3–5-in.-wide, semidouble to fully double blossoms that some say resemble small peony blooms. Flowers come in white, cream, and many shades of yellow, orange, red, pink.
All types are good in the ground or in pots. Tuberous roots are hardy to 10°F/–12°C; in Zones 4 to 9 and 12 to 31, plant in fall for bloom in winter, early spring. Beyond the hardiness range, plant in spring as soon as the ground is workable; or start roots indoors 4 to 6 weeks before the usual last-frost date. Nurseries sell tuberous roots of various sizes; all produce equally large blossoms, but bigger roots yield a greater number of flowers.
Grow in full sun, in organically enriched, very well-drained soil (if necessary, plant in raised beds). Set roots with prongs down, 2 in. deep (1 in. deep in heavier soils) and 6–8 in. apart. Water thoroughly, then withhold water until leaves emerge. Birds are fond of ranunculus shoots; protect sprouting plants with netting or wire. Or start plants in pots or flats, then set them in the garden when they’re 4–6 in. tall—too mature to appeal to birds. (You can also start with nursery-grown seedlings.) Remove faded flowers to encourage more bloom.
When flowering tapers off and leaves start to yellow, stop watering the plants and allow the foliage to die back. Where tuberous roots are hardy in the ground, they can be left undisturbed—as long as the soil can be kept dry during summer. However, most gardeners throughout the West dig plants when foliage turns yellow, cut off the tops, let roots dry for a week or two, and store them in a cool, dry place until planting time.
These annual and perennial plants are grown as herbal remedies and for culinary use.
The hardier species are native to cold-winter regions of Europe and Asia, where they bloom with winter...