doubleflowered

Doubleflowered is a term used in horticulture and botany to describe flowers that possess more petals than the typical form of the species or cultivar. It is a morphological trait rather than a taxonomic category, and it occurs in many ornamental plant groups, notably roses, carnations, peonies, camellias, and ranunculus. Doubleflowered forms are often developed through selective breeding or arise from mutations that alter floral organ identity, causing stamens and sometimes carpels to be converted into petal-like structures.

Physiological and reproductive implications: The proliferation of petals can obscure the reproductive organs, reducing fertility and seed production in many doubleflowered varieties. Many are sterile or produce few viable seeds, and propagation is usually vegetative (by cuttings, divisions) rather than from seed. Some doubleflowered taxa retain partial fertility, especially when mixed with single forms, but this is variable.

Cultivation and use: The doubleflowered phenotype is prized for ornamental value, providing a fuller, more conspicuous bloom. It has been a focus of breeding since at least the 18th–19th centuries in roses and other ornamentals. Plant breeders select for petal number, form, scent, and vigor while balancing disease resistance and environmental tolerance.

Terminology: In English, the trait is commonly described as double-flowered or doubleflowered; hyphenation varies by region. The term describes morphology alone and should not be confused with taxonomy.