Seedlings and young plants of lenten rose (Helleborus orientalis Lam.) were grown for two years (2006–2007) in containers on peat substrate which was deacidified with calcium carbonate at doses (g∙dm^-3) of 2.5, 5.0, 7.5 and 10.0. Within each dose of CaCO₃ plants were divided into two groups, of which one was fertilized with a lower (0.1%) and the other with a higher (0.3%) concentration of Peters Professional PL Special (15:11:29). The CaCO₃ dose applied to deacidify high moor peat had a significant effect on plant height irrespective of their age. In the first and second year of pot cultivation the tallest plants were produced on a substrate to which calcium carbonate was added at 2.5 g·dm^-3 CaCO₃, while the lowest at 10 g·dm^-3 CaCO₃. The number of leaves and flowering of lenten rose did not depend on the amount of calcium carbonate introduced to the substrate. Fertilization of lenten rose cv. ‘New Hybrids F1’ with Peters Professional PL Special (15:11:29) at a higher concentration (0.3%) made it possible to produce taller plants, with a larger number of leaves, and earlier and more abundant flowering.

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