<p><i>Moringa oleifera</i> is widely recognised for its nutraceutical potential, particularly due to its rich nutritional and bioactive composition, traditionally used in Angola. This study aimed to evaluate the effects of edaphoclimatic conditions on phenolic compound content of <i>M. oleifera</i> leaf and their influence on biological activities. The leaves were analysed for their phenolic profile, antioxidant activity measured by the DPPH method, anti-inflammatory activity via lipoxygenase inhibition, and antibacterial efficacy against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> across different harvest periods over two consecutive growth cycles (years from 2022 to 2023) at Luanda city. The results indicate that environmental factors, particularly high solar radiation and moderate soil moisture during late summer, just before the vegetative growth phase, significantly enhance phenolic compound accumulation. Key bioactive compounds, including gallic and caffeic acids, were more abundant during this period, contributing to increased antioxidant (128&#xa0;µg/mL, IC₅₀) and anti-inflammatory (64&#xa0;µg/mL, IC₅₀) activities. Additionally, antibacterial activity was significantly improved, particularly against <i>E. coli</i> bacteria (12&#xa0;mm), supporting the correlation between higher phenolic content and enhanced antibacterial activity. While climatic conditions were the primary determinants of phenolic biosynthesis, soil properties such as organic matter and potassium levels also played a supportive role. These findings underscore the importance of optimising harvest strategies to enhance the nutraceutical and pharmaceutical potential of <i>M. oleifera</i> leaf. By aligning cultivation practices with seasonal conditions, the bioactive compound yield can be maximised, improving its application in medicinal and functional food.</p>