This article describes how Taiwanese farmers adopted irrigation pumps to enhance their livelihoods under the shifting relationship of sugar and rice production in late colonial Taiwan. I argue that farmers utilized commercial technologies to make a living and prosper within the established order of Japanese colonial rule. With allocated procurement districts granting exclusive purchasing rights over sugarcane, sugar companies maintained substantial influence over sugarcane cultivation. However, with the proliferation of Penglai rice and new agricultural implements, the situation of the farmers changed substantially. Serious problems in the sugar industry due to economic depression and the rising price of rice in the 1930s led farmers to shift from sugarcane to rice cultivation by introducing a variety of pumps. Those with the means installed new motor pumps, while others independently constructed wind pumps by combining newly introduced parts with older techniques. Despite a prohibition by the colonial government, farmers continued installing pumps until the government established a planned economy in preparation for war. Moreover, distribution of pump capacity through both sales and sharing shows that Taiwanese farmers sought to maintain an informal yet significant cohesion throughout the process of agricultural commercialization. By focusing on the social dynamics surrounding agricultural technologies, this article challenges simplistic portrayals of technology transfer from Japan to the colonies.