Abstract

Geisha coffee is one of the most highly regarded Arabica coffee cultivars due to its outstanding sensory and high market value. However, this cultivar is often considered highly sensitive to environmental conditions. Therefore, this experiment aimed to evaluate the relationship between the absolute growth rate (AGR) of Geisha coffee (Coffea arabica L.) seedlings and air temperature under contrasting environmental conditions. The experiment was conducted at three locations: a greenhouse at the Department of Agronomy, Faculty of Agriculture, Kasetsart University (BKK), Doi Pui Research Station, Chiang Mai Province (DP), and Phu Thap Boek Research Station, Phetchabun Province (PTB). Plant height was measured at 3-month intervals from October 2024 to October 2025, and AGR was calculated for each growth interval. Air temperature data were obtained as monthly mean values from meteorological stations located nearest to each experimental site and were used to analyzed the relationship between growth and temperature. The results showed that AGR was positively correlated with air temperature at all locations, indicating that higher temperatures were associated with increased rates of stem elongation in Geisha coffee seedlings. These findings enhance the understanding of growth dynamics of Geisha coffee under different thermal conditions and provide useful information for site selection and management practices for coffee production in Thailand.