Background. The aim of the study was an assessment of the effect of using various sowing methods and types of applied biostimulators on pre-dormancy plant habit as well as on overwintering of three types of winter rape cultivars. Material and methods. A field experiment was carried out in a split-split-plot design in three replications. The studied factors included: I-three cultivars of winter rape: Monolit (population cultivar), PR 44D06 (restored hybrid cultivar with a semi-dwarf type of

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... h), PT 205 (restored hybrid cultivar with a conventional type of growth); II-two sowing methods: row spacing of 22.5 cm (row sowing-sowing density of 60 seeds per 1 m 2), row spacing of 45.0 cm (single seed sowing-sowing density of 40 seeds per 1 m 2); III-three types of applied biostimulators: control variant (without an application of biostimulators), Tytanit ® biostimulator, Asahi ® SL biostimulator, Silvit ® biostimulator. Results. Biostimulators applied in the experiment affected an increase in the number of leaves per rosette, root collar diameter, height of elevation of shoot apex as well as taproot length compared with the control plot. The highest values of morphological traits of plants determined in autumn before inhibition of growth as well as plants most complete winter survival were obtained under conditions of spraying with Asahi SL biostimulator, applied at the stage BBCH 13-15. The population cultivar overwintered better in comparison to the two heterotic cultivars, produced rosettes with a higher number of leaves (on average 8.4 leaves), a thicker root collar (on average 7.9 mm), as well as a longer taproot (on average 17.3 cm).The smallest plant losses occurred in cultivar Monolit after winter dormancy. Sowing method did not affect this trait of plant habit. Conclusion. Asahi SL biostimulator significantly affected an increase in all morphological traits of the leaf rosette determined in autumn before inhibition of growth, when compared with the control variant. The restored hybrid morphotypes: PR 44D06 and PT 205, compared with the population cultivar Monolit, were characterized by a poorer autumn development of the leaf rosette. Diversified climatic conditions in the autumn-summer periods of vegetation and in the winter dormancy in the years of the research affected plant habit.