The genus Helleborus belongs to the family Ranunculaceae and comprises about 22 species, which are distributed over different parts of Europe and West Asia. In Poland, only H. purpurascens is native and it occurs in the Western Bieszczady Mountains. Hellebores are popular as ornamental cut flowers and medicinal plants in Europe and the USA. Conventional propagation by seeds or division has a low multiplication rate and is time-consuming. Vegetative propagation is necessary to maintain the desirable characteristic of a particular hellebore cultivar. Although some research on tissue culture of hellebores has been published, effective commercial micropropagation of these species has not been attained because cultivation in vitro is still very difficult. This review presents the progress in Helleborus species propagation in vitro for its commercial production. The efficacy of hellebore micropropagation (initiation and stabilization of culture, multiplication and rooting in vitro and acclimatization ex vitro) has been influenced by several factors, such as: type of initial explants, genotype, growth regulators, and environmental factors (temperature, sucrose, nitrogen salts, phosphorus). The genotype-dependence of multiplication and rooting in vitro, and acclimatization ex vitro of some Helleborus species has been presented.

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