Analyzing Growth Reactions of Herbaceous Plants for Irrigation Management

Background and objective: The purpose of this study was to provide guidelines for irrigation management by analyzing the effects of soil moisture on the growth characteristics of herbaceous plants in green infrastructure. Methods: In a rain shelter greenhouse, the growth performance of nine species of experimental plants was assessed under different soil moisture contents (20%, 15%, 10%, 5%, and 1%) for about 5 months to analyze plant growth characteristics due to soil humidity. Methods to determine plant growth conditions include surveying growth conditions of the crowns, stems, leaves, flowers and fruits on the aerial part and surveying growth conditions of the roots in the underground part. Results: The results showed that Mukdenia rossii and Astilbe rubra grew well at 15% moisture content with irrigation intervals of 10 and 13 days, respectively. Soil moisture content of 10% with irrigation intervals of 13 and 17 days was appropriate for Sedum kamtschaticum and Pachysandra terminalis. Similarly, Aquilegia japonica and Liriope platyphylla grew well at 15% moisture content with irrigation intervals of 10 and 17 days. However, Ligularia stenocephala grew well-developed stems and roots at 1% soil moisture content and an irrigation interval of 25 days, while the optimum conditions for Lythrum anceps were 5% moisture content and an irrigation interval of 8 days. Conclusion: Although a limited number of experimental plants were used in this study, this study could propose an appropriate irrigation cycle for planting on artificial soil substrates. Based on these results, it is possible to plan suitable planting designs considered irrigation cycles.