Efficient sowing techniques ensure proper crop establishment and enable optimal utilization of resources, thereby enhancing crop productivity, reducing production costs, and improving overall farm profitability. Although quinoa is a low water-requirement crop, it responds significantly to well-planned irrigation regimes. To develop suitable irrigation schedules for quinoa under different land management in rice fallows, a field experiment was conducted for two consecutive years (2022–2023 and 2023–2024) at the ICAR–Indian Institute of Water Management, Bhubaneswar Research Farm. The experiment included two sowing techniques in the main plots (L1: Broad Bed and Furrow; L2: Flat Beds) and three irrigation schedules in the subplots (I1: Irrigation at branching, primordial initiation, flowering, and grain filling; I2: Irrigation at branching, primordial initiation, and grain filling; I3: Irrigation at branching and flowering). Sowing quinoa on broad bed and furrow (BBF) resulted in significant increases in grain yield (12.6%), biological yield (11.9%), land productivity (13.4%), and energy use efficiency (12.5%) compared to flat beds. The BBF method also achieved a higher net return (US $531/ha), benefit-cost ratio (1.82), physical water productivity (0.79 kg/m3), and economic water productivity (US $0.67/m³). Irrigation scheduling at all four critical growth stages (I1) led to an increase in grain yield (1.57 t/ha), higher net return (US $686/ha), Benefit/Cost “B:C” ratio (2.05), and improved water productivity (0.66 kg/m³ and US $0.57/m³ economic water productivity). Therefore, appropriate land management combined with optimal irrigation scheduling is essential for realizing the full yield potential of quinoa in the rice ecosystems of Eastern India.