This study investigates the combined effects of arbuscular mycorrhizal fungi (AMF) inoculation and leaf leachate application on various morphological, physiological, and reproductive traits of Anthemis cotula L., an invasive species in Kashmir Himalaya. Results from a greenhouse experiment reveal a significant synergistic effect of AMF and leaf leachate on plant traits, particularly during the later growth stages. Specifically, plant height increased significantly under the combined treatment of AMF and the highest concentration of leaf leachate (AMF+AL2), with plants reaching a height of 23.13 cm. In contrast, leaf leachate alone suppressed growth, which was mitigated by the addition of activated charcoal. Root dry mass showed the highest increase under leaf leachate treatments, while shoot dry mass was significantly enhanced under the combined treatment of AMF and leaf leachate, reaching 4.37 g/plant. The number of lateral branches also increased significantly under the combined treatment of AMF and leaf leachate. Photosynthetic rate and stomatal conductance were notably higher in plants treated with AMF and leaf leachate, indicating improved physiological performance. Furthermore, the extent of AMF colonization was positively correlated with phosphorus content, with the highest phosphorus accumulation observed in AMF and leachate treated plants. These findings suggest that the interaction between AMF and leaf leachate plays a crucial role in the growth and invasiveness of A. cotula, influencing key traits like plant height, biomass allocation, and reproductive potential. The results underscore the importance of considering the combined effects of belowground and aboveground factors in understanding plant invasiveness. This study contributes to our understanding of the mechanisms that drive the success of invasive species, with implications for managing their spread and promoting ecological restoration.