This study evaluated the effects of organic and chemical fertilizers on the vegetative yield and essential oil quality of Prangos ferulacea (L.) Lindl, a medicinal plant cultivated in a cold semiarid climate. Treatments comprised a control (no fertilizers), sheep manure (30 and 60 t/ha), vermicompost (10 and 20 t/ha), their combinations (15 t/ha sheep manure + 5 t/ha vermicompost; 30 t/ha sheep manure + 10 t/ha vermicompost), and chemical fertilizers (100-50-50 kg/ha N-P-K). The application of 30 t/ha sheep manure produced the highest vegetative yield (3267.9 kg/ha) and essential oil yield (23.85 kg/ha), with an essential oil content of 0.154%. Vermicompost at 10 t/ha maximized gamma-terpinene content (62.61%), while the combination of 30 t/ha sheep manure and 10 t/ha vermicompost enhanced thymol content (21.8%). Organic fertilizers consistently outperformed chemical fertilizers in both yield and oil quality, promoting sustainable agricultural practices by improving soil health and minimizing environmental risks. These findings highlight the efficacy of organic fertilization in optimizing the productivity and bioactive compound profiles of P. ferulacea, offering a viable strategy for medicinal plant cultivation in resource-constrained environments.