The effect of planting seed corms of elephant foot yam (Amorphophallus campanulatus Blume) at 15-day intervals from February to July under irrigation on growth, corm development, and yields was investigated. Time of planting played a crucial role for sprouting of elephant foot yam. Corms planted from March to April sprouted faster and were followed by better plant vigour due, possibly, to higher temperatures immediately after planting and other climatic factors like higher rainfall and relative humidity. As corm bulking was most rapid between June and August the establishment of full plant vigour with high biomass before June was necessary to allow a longer period of maximum bulking and to obtain higher corm production. Planting should therefore be restricted to the period and mid-March to mid-April to obtain maximum corm production.