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Weed control constitutes one of the main cost items in carrot production. Field study was conducted at the field station farm, University of Nairobi in 2010 period with the aim of developing a cost-effective strategy of managing weeds and increasing the competitive ability of the crop against weeds. The weed control strategies tested were; black plastic mulch, grass mulch, herbicides (Linuron and oxyfluorfen), mulch / herbicide combinations, foliar feed fertilizer/ one hand weeding combinations, foliar feed fertilizer / 1.5 cm grass mulch combination, hand weeding every two weeks, famers practice (two hand weeding), and control (no weeding). Pigweed (Amaranthus hybridus), black jack (Bidens pilosa) and oxalis (Oxalis latifolia) were the most common weeds in the experimental plots. For instance the occurrence of pig weed in a quadrant was 67 % compared to oxalis 16%, black jack 7%, yellow nutsedge 8%, and chick weed 3%. The efficacy of weed control was significantly (P ≤ 0.05) different among the methods tested. Black polythene was the most effective method with 99.2 % weed control compared 78% in plots treated with a herbicide (Linuron), which is at par with 19 % two hand weeding (farmers practice) .Carrot yield was (33984 kg/ha) in plots where weeds were controlled using black polythene compared to (26544kg/ha) and (14168 kg/ha) under the herbicide and farmer practice, respectively. Application of foliar feed fertilizer increased tolerance in the crop against the effect of weed competition. It was concluded that mulching is an effective strategy of reducing weed growth in carrots. Foliar feed application imparts competitive ability in the crop against weeds.