This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Of the many species known, only two or three are cultivated occasionally for market. The double-flowered variety of R. aconiti-folius, with pure snow-white flowers popularly known as "White Bachelors' Buttons", "Fair Maids of France", and "Fair Maids of Kent", is one; and the double-flowered variety of the Common Buttercup, R. acris, is the other. The latter has beautiful golden-yellow flowers. Both kinds grow 12-24 in. high, and will flourish in any damp garden soil. They are easily increased by division in autumn, and the flowers sometimes sell well. There is also a double-flowered variety of R. bulbosus.
The Asiatic, Turkey, and Persian Ranunculuses (varieties of R. asiaticus) have tuberous fanged roots, and produce fine double flowers of various shades of orange, yellow, rose, pink, purple, and intermediate shades. Although very popular in private and public gardens, they are not generally grown for market in the British Isles, probably owing to the fact that the blooms are imported in thousands early in the year when they cannot be had in the United Kingdom, and later on the competition of other home-grown produce would render the cost of cultivation, etc, unremunerative.
Nurserymen do a limited trade in certain species of Ranunculus for borders and rock gardens, among the most important being alpestris, 3-6 in., white; amplexicaulis, 3-12 in., white; cortusoefolius, 3-5 ft., yellow; Lyalli, 2-4 ft., white; gramineus, 6-12 in., yellow; and montanus, 6-8 in., yellow.