Year-Round IoT-Based Characterization of Forest Microclimate for Sustainable Medicinal Plant Cultivation

Forest microclimate strongly influences medicinal plant growth and habitat suitability; however, year-round characterization of forest microclimate for medicinal plant cultivation remains limited. This study presents a year-long, multi-station microclimate dataset and evaluates its potential for preliminary suitability assessment. Three monitoring stations (Pt1–Pt3) were deployed within the Plant Genetic Conservation Project under the Royal Initiative (RSPG), Thailand. Air temperature and relative humidity were continuously monitored at 30-min intervals from January to December 2025 using an Internet of Things (IoT)-based system. We used descriptive statistics, coefficients of variation (CV), repeated-measures analyses, and adjusted pairwise comparisons to evaluate year-round, seasonal, and site-specific microclimatic variabilities. Significant spatial differences were observed among the monitoring stations (p < 0.05). Pt3 exhibited the lowest annual mean temperature (26.05 °C), the highest relative humidity (80.60%), and the lowest environmental variability (CV = 16.41%), whereas Pt2 showed the highest temperature (30.72 °C), the lowest humidity (60.83%), and greater variability. A relative microclimatic comparison showed that Pt3 was cooler, more humid, and more stable; Pt1 exhibited intermediate conditions; and Pt2 was warmer, drier, and more variable. These findings characterize relative temperature–humidity conditions among the monitored sites and provide baseline information relevant to future species-specific assessment of medicinal plant cultivation.