Growth of Veronica nakaiana and Veronica pyrethrina under Different Shading Levels

Veronica nakaiana and V. pyrethrina are Korean native plants that could be developed as ornamental plants. This study aimed to investigate the growth of these plants at different shading levels and to suggest appropriate shading conditions. In previous studies, controlled soil moisture during shading experiments have been reported. Thus, we used the automated irrigation system by frequency domain reflectometry (FDR) sensors to keep similar soil moisture throughout the shading treatments. The shading treatment consisted of four treatments (0%, 55%, 75%, and 95%) using black mesh tarps. During the experiment, the soil moisture temporarily increased when it rained, but the target soil moisture was generally maintained under the automated irrigation system. Under no shading condition, the growth of V. nakaiana was good based on the number of leaves and dry weight, and in quantum yield, no shading condition showed the highest value than all other treatments. Under 55% shading conditions, V. pyrethrina had good growth, and the quantum yield also showed high values.