Shoot tips of Tibouchina urvilleana Cogn. were cultured 4 weeks in vitro in modified Murashige and Skoog (MS) [1962] medium supplemented with growth retardants: paclobutrazol – 0.1, 0.5, 1.0, 5.0 mg∙dm^-3, flurprimidol – 0.1, 1.0, 5.0 mg∙dm^-3, chlorocholine chloride (CCC) –5.0, 50.0, 250.0 mg∙dm^-3. Explants cultured on the medium without growth substances were used as a control. Rooted microcuttings were transferred to the greenhouse and transplanted into a mixture of 1 peat :  1 perlite, where they were grown for 5 weeks. Plants were then cultivated in a peat substrate during another 5 weeks. Acclimatization of rooted shoots in the greenhouse was affective in 92.5–100%. The survival of plants was lowest when microcuttings were previously cultured on medium with flurprimidol at 5.0 mg∙dm^-3. Cultivation of Tibouchina urvilleana shoots in vitro on media with various growth retardants had a significant effect on the further growth of plants ex vitro. Paclobutrazol and flurprimidol at 5.0 mg∙dm^-3 inhibited very strong growth of plants after 10 weeks of growth ex vitro.

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