Assessing the Impact of Nitrogen Trade‐Off Between Coffee Tree Productivity and Bean Sensory Attributes to Produce Australian ‘Specialty Coffee’

Effective nitrogen management is essential for sustainable coffee production and enhanced yield. This study evaluated the effects of five nitrogen application rates (per annum; N1: 120 kg/ha, N2: 240 kg/ha, N3: 360 kg/ha, N4: 480 kg/ha, N5: 600 kg/ha) applied in equally distributed monthly rates over 2 years, from flowering to harvest, on Coffea arabica L. field performance. The highest mean cherry yields (tons/ha) were observed under N1–N3 treatments at both time points (T1 and T2), significantly outperforming controls. Yield gains per tree ranged from 45% to 70% at T1 and 30%–50% at T2. Cup quality also improved, with mean ‘cup scores’ reaching 82.4–83.8 at T1 and 81.2–84.1 at T2 under N1–N3 treatments, compared to control ‘cup scores’ of 73.5 and 74.1 (T1 and T2, respectively). Bean flavour enhancement showed trait gains of 15%–40% at T1 and 10%–40% at T2. These findings highlight the importance of optimised nitrogen input (particularly N2 and N3) for improving both productivity and sensory quality in C. arabica, offering valuable insights for sustainable coffee agronomy.