The effectiveness of the combined use of zinc, boron, and magnesium on tea plantations in the humid subtropics of Russia

Federal Research Centre the Subtropical Scientific Centre of the Russian Academy of Sciences, Yana Fabritsiusa st. 2/28, 354002 Sochi, Kransnodar Region, Russia

^* Corresponding author: kriptozoorxon@mail.ru

Abstract

It was found that the simultaneous root application of zinc, boron and magnesium against the background of macro fertilizers in the studied period 2011-2023 provided a stable increase in yield. The yield of tea leaves was on average 28% higher than the control (5.9 and 4.6 t/ha, respectively). In favorable years, the studied variant showed a significant increase in yield by 32% compared to the control one. The yield in more difficult weather conditions (spring frosts and summer drought) on the variant of joint root application of elements (Zn+B+Mg) against the background of macro fertilizers averaged 3.9 t/ha, which was 22.3% higher than the control. During these years, one of the key factors determining the productivity of the tea leaf was the amount of precipitation during the growing season (March–September), amounting to 650 mm. The harvesting of tea leaves in unfavorable years took place unevenly, often one of the months of the leaf-collecting period yielded about 50% of the total harvest. The combined use of zinc, boron, and magnesium for the studied period 2011–2023 was economically profitable, a significant increase in the yield of green tea leaves provided a level of profitability of 20%.