ABSTRACT
The genus Ranunculus comprises about 400 species of annual and perennial herbs. The garden ranunculus R. asiaticus L., popular as a spring and summer flower in English and Belgian gardens of the 18th and 19th century, is grown commercially as a winter and spring cut-flower crop mainly in areas with a Mediterranean climate, either out-of-doors or in plastic structures. The garden ranunculus is a xerophytic perennial with dimorphic roots, filiform absorptive ones with laterals and bunched short-cylindrical tuberous roots which form the “corm” or “claw”. In an environment in which wild ranunculus flowered in February and commercial “Tecolote Hybrid’’ varieties in April, crosses between the two flowered in the middle of March. Cutflower ranunculi are usually planted as 1-year corms. The lesser spearwort Ranunculus flammula L., which flowers from June to August under natural conditions, was found by P. Chouard to flower incessantly under continuous daylight with its flower stems becoming thinner and its flowers smaller to miniscule.
