The cultivation system with cover crops as living mulches is growing in importance in the worldwide agriculture as it combines an economical effect with pro-ecological and soil protecting activities. The plant species tested in the research were not frost resistant: buckwheat, millet, white mustard and berseem clover. A control were the plots without cover crops. The intercrops were sown in the first decade of August, in autumn a grown biomass was a living mulch, and after being damaged by frost in spring, the mulch was covering ground surface. Winter garlic bulbs were planted in grown biomass of cover plants, in the first decade of September. In the first decade of November and in the first decade of April, the selected soil parameters were determined in the soil layer of 0–10 cm: actual soil moisture (%), soil bulk density (Mg · m–3), total porosity (%) and water stability of soil aggregates (%). The harvest of garlic was conducted in the first decade of July. Cover crops mulches had an influence on soil physical properties. In spring, the soil from plots with cover crops mulching characterized with the highest moisture, higher total porosity and soil aggregates stability as well as lower soil bulk density. In comparison to the control cultivation of winter garlic, without cover crops, the effect of plants used for mulching on marketable yield was not observed. Garlic plants intercropped with the white mustard mulch formed leaves and bulbs of higher weight in comparison to cultivation without cover crops.