<i>Azolla microphylla</i>, a rapidly growing aquatic fern with the unique ability to fix atmospheric nitrogen, presents significant potential for sustainable agriculture. Despite its nitrogen-fixing prowess, challenges persist in optimizing biomass production, prompting a detailed exploration of influential factors in this study. This paper addresses the persistent challenge of optimizing nitrogen-rich biomass production in <i>Azolla</i> cultivation. Employing a split-plot experimental design, the study investigates the influential factors of shading percentage (N) and water depth (G) in <i>Azolla</i> growth, systematically ranging from 0% (full sunlight/N1) to 75% (N3) shading percentages and 2.5 cm (G1), 5.0 cm (G2), and 7.5 cm (G3) water depths. In addition to assessing growth and production outcomes, this study explores the nitrogen content in <i>Azolla</i> under three different conditions: fresh, dried, and composted <i>Azolla</i>. Findings unveil the significant influence of shading percentage and water depth on <i>Azolla</i> growth, with the N1G2 treatment identified as the optimal condition for achieving maximum biomass production. Set against the backdrop of tropical agriculture, specifically within the high temperatures in Indonesia, our study underscores the resilience of <i>Azolla</i> to elevated temperatures, highlighting its potential as a nitrogen-fixing agent. Notably, fresh <i>Azolla</i> closely matches urea in nitrogen content, suggesting its potential as an organic fertilizer substitute for urea. This research sheds light on the critical challenges surrounding nitrogen-rich biomass production from fresh <i>Azolla</i>, emphasizing the necessity of temperature resilience and water depth optimization. The insights provided hold significance for tropical agriculture practices seeking to harness the potential of <i>Azolla</i> as a free-air nitrogen fixator.
