Impact of Agrotechnical Methods on the Development and Economic Indicators of Elsholtzia ciliata (Thunb.) Hyl.

Abstract

Elsholtzia ciliata (Thunb.) Hyl., commonly known as Vietnamese balm, is an aromatic and medicinal plant valued for its essential oil rich in biologically active compounds. This study aimed to evaluate the influence of sowing time and irrigation regime on the growth, productivity, and essential oil content of E. ciliata genotype No. 23-60 cultivated under the climatic conditions of Cherkasy Oblast, Ukraine. Field experiments included phenological observations, morphometric measurements, and assessment of biomass and essential oil yield under three watering regimes (natural, moderate, and intensive drip irrigation) for two sowing dates. The total vegetative period was 144 days for the first sowing and 131 days for the second. Plants grown under intensive watering showed enhanced growth parameters and higher biomass production compared with those under natural irrigation. The highest green mass and inflorescence yields were recorded at the first sowing with intensive drip irrigation, while moderate irrigation provided the maximal leaf yield. Essential oil content in the mass-flowering phase ranged from 0.45–0.82% for the first sowing and from 0.57–0.59% for the second, depending on the water regime. The results indicate that early sowing combined with intensive drip irrigation ensures optimal growth and oil accumulation in E. ciliata. These findings may be useful for developing agrotechnical recommendations and for further breeding aimed at selecting genotypes with improved essential oil yield and adaptability to different environmental conditions.