A research work was conducted at Horticulture Farm, Sriniketan during kharif 2013 to study the growth performance of five kharif onion cultivars (Agrifound Dark Red, Arka Kalyan, Arka Niketan, Indam Marshal and Red Stone) in four planting dates (15^th August, 30^th August, 15^th September and 30^th September) under Red and Laterite Zone of West Bengal. Overall growth performance of onion plants were improved as the planting dates were shifted from August to September. Maximum plant height, number of leaves and neck diameter were recorded on 30^th September planting followed by planting on 15^th September. Agrifound Dark Red and Indam Marshal excelled other cultivars in different growth parameters. Onion cultivars Agrifound Dark Red or Indam Marshal were suggested to be planted during September to get vigourous plants, which assumed to give more bulb yield or growers may also sell the plants as green onion in the market.