Three trials were conducted at the Agriculture Canada Research Station, Agassiz, B.C., to assess the influence of row cover and plant population density treatments on plant growth and fruit yield of bell peppers (Capsicum annuum L.). Transplants were grown on raised beds covered with black polyethylene mulch. Plants were covered with slit-polyethylene tunnels, or not covered, and were planted at five population densities (1.4, 1.9, 2.8, 5.6 and 11.1 plants m - 2 ). Row covers and higher population densities significantly enhanced total fruit yield. Fruit yield per land area increased with increasing population density. Significant treatment effects occurred early in growth but interactions of row covers and population density were not significant. Functional plant growth analysis indicated that row covers increased absolute growth rates but decreased unit leaf rates. High population densities decreased absolute growth rates but both treatments promoted shoot biomass accumulation per unit land area. Yield component analysis indicated that the inverse of leaf weight ratio contributed significantly to row cover effects on yield variation. Node number was the most important yield component contributing to population density effects and it showed the greatest response to population density of all yield components.