Chrysanthemum mutants can be chimeras. The regeneration in vitro of adventitious shoots from ligulate florets can lead to the separation of chimera components, resulting in producing a new cultivar. There was determined the effect of various factors on the number and length of shoots regenerating in vitro from ligulate florets of Chrysanthemum × grandiflorum (Ramat.) Kitam. ‘Cool Time’. The ligulate florets were inoculated on the MS [1962] medium supplemented with cytokinin (0; 4.44; 8.88; 13.32; 22.20 µM∙dm^-3 BAP; 4.65; 23.23; 46.47; 69.70 µM∙dm^-3 KIN) and auxin (0; 0.54; 1.08; 1.61; 2.69 µM∙dm^-3 NAA). Most shoots regenerate when 8.88; 13.32 µM∙dm^-3 BAP or 69.70 µM∙dm^-3 KIN and 2.69 µ M∙dm^-3 NAA or 8.88 µM∙dm^-3 BAP and 1.61 µM∙dm^-3 NAA are supplemented. Adding 0.29; 1.44 or 2.89 µM∙dm^-3 GA₃ to the MS medium with 8.88 µM∙dm^-3 BAP and 2.69 µM∙dm^-3 NAA limits the shoot regeneration efficiency and does not stimulate their elongation. An increase in the shoot number and length is affected by the subculture of regenerating ligulate florets from the MS medium containing 8.88 µM∙dm^-3 BAP and 2.69 µ M∙dm^-3 NAA on the medium with 2.89 µM∙dm^-3 GA₃ and 2.69 µM∙dm^-3 NAA. There were found no differences in the number and length of shoots regenerating on ligulate florets inoculated on solid or in liquid MS medium with 8.88 µM∙dm^-3 BAP and 2.69 µ M∙dm^-3 NAA. The subculture of regenerating ligulate florets from the solid into liquid medium increases the number of regenerating shoots and stimulates their elongation growth, however these shoots are deformed.

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