Onion nursery is severely affected by the weed which hampers the growth of seedlings and further delayed in transplanting and thereby yield. For obtaining potential yield of onion, producing and transplanting of healthy seedlings and timely control of complex weed flora is necessary in onion nursery. An experiment was carried out during two consecutive Rabi (winter) season of the year 2020-21 and 2021-22 at B. A. College of Agriculture, Anand Agricultural University, Anand, Gujarat (India). In this study, total 12 different treatments each in nursery and in transplanted onion were tested in a randomized block design (RBD) having three replications. Early post-emergence application (EPoE) of propaquizafop + oxyfluorfen (pre-mix) 43.75 + 105 g/ha, oxyfluorfen 80 g/ha EPoE, pendimethalin 300 g/ha as pre-emergence (PE) and twice hand weeding at 15 and 30 days after sowing (DAS) significantly reduced the dry biomass of weeds, recorded higher weed control efficiency, fresh weight of 100 seedlings, higher number of transplantable seedlings and better economic returns than rest of the treatments. All the herbicides applied in onion nursery were found safe for succeeding wheat, chickpea and mustard crop under bioassay study. In transplanted onion, pre-plant incorporation of pendimethalin 580.5 g/ha followed by (fb) oxyfluorfen 120 g/ha applied as post-emergence (PoE) and pre-emergence (PE) application of oxyfluorfen 120 g/ha fb propaquizafop + oxyfluorfen 43.75 +105 g/ha applied as post-emergence and propaquizafop + oxyfluorfen 43.75 +105 g/ha as post-emergence recorded significantly lower weed dry biomass, higher weed control efficiency, onion bulb yield, net return and benefit cost ratio.