Experiments in small plots were performed to cultivate Hypericum perforatum L. var. angustifolium DC on light soil and at a sunny location in Bratislava. In the 1 st year of vegetation the herb was not harvested. Harvests were made in the 2 nd and 3 rd years of vegetation and later plants died. In the course of the vegetation year it was possible to carry out three harvests on the rule. The 1 st one was made just prior to blooming or at the stage of the onset of blooming, and only the blooming top parts were collected. The yield of the dry tops varied in dependence on the vegetation year, conditions of the location, age of the plants, and the date of the 1 st harvest. From the two-years old plants, a whole-year yield of 8.12–14.87 kg.10 m –2 of dry tops and from the three-years old plants, 8 kg . 10 m –2 , was obtained. The content of hypericin varied from 0.06 to 0.13 %, and 60% ethanol extracted 21.7–27,9 % of substances.

        Key words: Hypericum perforatum L. – cultivation – hypericin – extractive substances