The research investigates the allelopathic influence of Euphorbia hirta extracts on the germination and seedling development of various cucurbit species, including Bottle gourd (Sp. A), Winter melon (Sp. B), Ridged gourd (Sp. C), Sponge gourd (Sp. D), Bitter gourd (Sp. E), Snake gourd (Sp. F), Muskmelon (Sp. G), and Pumpkin (Sp. H). The experimental design incorporated the use of both aqueous and methanol extracts of E. hirta, applied at different concentrations, with distilled water employed as the control. The findings reveal that the methanolic extract of E. hirta significantly impedes both the germination process and the subsequent growth of seedlings for all cucurbit species tested. For instance, at 12 days post-treatment, control groups exhibited high germination percentages (78%, 90.67%, 95.33% and 90% for Sp. A, Sp. C, Sp. D and Sp. E, respectively), which drastically declined with a 20% methanol extract concentration (23.33%, 18.33%, and 17.67% and 18.33% for the same species, respectively). Similarly, shoot and root length measurements indicated that higher concentrations of both extracts suppressed growth, with methanol extract showing a stronger inhibitory effect compared to the aqueous extract. Interestingly, Lower extract concentrations occasionally boosted shoot growth, revealing a hormetic effect. This two-fold response, notably in Pumpkin and Snake Gourd, illuminates the complexity of allelopathic interactions. The study suggests E. hirta extracts could serve as eco-friendly herbicides, urging further research to isolate their active components. This could lessen synthetic herbicide use, promoting sustainable agriculture and environmental protection.