Optimizing planting density for enhanced growth and yield of pennywort (Centella asiatica L.) in Central Vietnam

Pennywort is widely cultivated for its nutritional and medicinal benefits, yet optimal agronomic practices, particularly planting density, remain underexplored. Proper density management influences photosynthesis, microclimate, and yield. This study aims to determine the ideal planting density for maximizing pennywort productivity and quality in Hue, Vietnam. Field experiments were conducted to assess the responses of pennywort to different planting densities at Hue city, Central Vietnam in two cropping seasons in 2024. Six treatment combinations comprising four levels of inter (5, 10, 15, and 20 cm) and two levels of intra-row spacing (10 and 15 cm) were studied on the local pennywort variety. The treatments were arranged in a randomized complete block design (RCBD) with three replications. The results revealed that leaf area, fresh and dry biomass, as well as the yield of pennywort, were significantly affected by the plant density (p less than 0.05). Increasing planting density increased the total fresh and dry biomass and yield of pennywort in both cropping seasons; however, it reduced the leaf area. The highest economic yield (7.87-8.01 t/ha) and total fresh biomass yield (9.05-9.25 t/ha) were obtained using 10×10 cm (100000 plants/ha). Hence, 10×10 cm could be used as the optimum plant spacing to grow the local pennywort variety in the respective cropping seasons in alluvial soil of Hue city, Central Vietnam.