THE EFFECT OF ORGANIC FERTILIZATION ON PRODUCTIVITY AND BIOCHEMICAL COMPOSITION IN THREE CULTIVARS OF Lavandula angustifolia Mill. GROWN IN THE BUZĂU PLAIN

Abstract

A multiannual study (2020-2024) was carried out in the Buzău Plain to assess the impact of organic fertilization on productivity and biochemical composition in three cultivars of Lavandula angustifolia Mill. (‘Vera’, ‘Munstead’, ‘Codreanca’). The fertilization regime included organic nitrogen sources (blood meal, compost), phosphorus (natural phosphates), and potassium (mineral-origin potassium sulfate), with periodic supplementation of basalt rock meal. Growth and yield parameters (plant height, number of flowering stems, inflorescence mass, essential oil yield) were monitored alongside biochemical indicators (phenolic compounds, carotenoids, ascorbic acid). Significant cultivardependent differences were observed, with ‘Vera’ consistently showing superior performance in both productivity and secondary metabolite accumulation. Statistical analysis revealed strong correlations between the number of flowering stems and essential oil yield (r = 0.87), as well as between fertilization intensity and phenolic compound content (~40% increase from minimum to maximum dose). The findings demonstrate that organic fertilization plays a crucial role not only in sustaining floral yield but also in enhancing biochemical quality. This study underlines the synergistic effect of genetic background and sustainable nutrient management, offering practical recommendations for expanding organic lavender cultivation and improving the economic and therapeutic value of its raw material.