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The article deals with the growth variability assessment of spruce (Picea abies (L.) Karst.) in ortets and clone plantations of the 1st and 2nd generation growing on extreme mountain conditions. Measurements of growth distinguished half-sib progenies characterized by above-average of below-average growth on majority of sites during 5 years after outplanting. Progenies with above-average growth of normal growth but very good health state were chosen for more detailed assessment in clone plantation of the 2nd generation. Statistic tests proved significant influence of the origin (pertaining to particular clones) to height and diameter growth of spruces in the time of planting and after next 5 years. Intraclone variability (pertaining to particular ramets within a clone) was insignificant or nearly insignificant 5 years after outplanting. Assessment of growth features in clone plantation of the 2nd generation suggests that the use of vegetative propagation of vigorous spruces from ortets and clone plantations growing in mountain conditions is useful. Potentially stresstolerant clone mixtures obtained in this way can form the frame of newly established forest stands.