Eupatorium odoratum is known for its ability to resist nematode infestations that attack the root systems of banana plants. An aqueous extract of the leaves and stems of E. odoratum (named EEOL) represents a natural solution that we investigated for its potential to control the harmful nematode, Radopholus similis, in Cavendish banana plants. Our research into EEOL’s efficacy spanned two distinct environments: a micro plot experiment model and a field model. Various concentrations of EEOL were examined to assess its efficacy in alleviating R. similis infestations and in mitigating their adverse effects on Cavendish banana plants. In the micro plot experiment model, the concentration of the original solution, diluted at ratios of 1:30×, 1 : 16×, 1 : 8×, 1 : 4×, and 1 : 2×, ranged from 1.76 to 28.16 mg · ml ^-1. In the field model, the corresponding rates varied from 6.03 to 96.54 l · ha ^-1. Key parameters, including infection rates, root necrosis indices, plant growth metrics, percentage of fallen trees, and harvest yields, were meticulously monitored and assessed. The results demonstrated that EEOL significantly reduced infection rates ( p < 0.05), decreased root necrosis indices ( p < 0.05), and promoted increased plant height, pseudostem circumference, and leaf area ( p < 0.05) in both models. Furthermore, it lowered the percentage of fallen trees ( p < 0.05) and enhanced harvest yields ( p < 0.05) in the field model. Notably, observations in the field model revealed that EEOL, particularly at a dosage of 96.54 l · ha ^-1, exhibited effectiveness equivalent to the conventional chemical nematode control method, fenamiphos ( p > 0.05). The study’s findings underscore the promising potential of EEOL in effectively managing R. similis infestations and improving the yield and quality of Cavendish banana plants. The aqueous extract of the stem and leaves of E. odoratum emerged as an effective nematode management solution for banana cultivation, in both the micro plot experiment and field conditions.