In peasant studies as well as agricultural and economic history, little is known about the diffusion of new agricultural knowledge in peasant regions and the ways in which smallholding families gained confidence to adopt new approaches to their farming activities. New agricultural innovations—especially those that required substantial cash outlays—were kept at arm’s length because of the outcome’s uncertainty, which could harm the survival strategies of smallholding peasants. Tis article elaborates on the spread of two innovative fertilizer improvements—animal urine and lime—in the eighteenth-century smallholding economy of Inland Flanders. It argues that farm size and social relations between smallholding peasants and larger farmers played a pivotal role in the dissemination of fertilizer knowledge. Smallholders did not stick to the safe application of current manures but instead adopted these new innovations after they saw the benefits on pioneering large farms. Tis study, therefore, confirms much about our understandings of a peasant behavior of risk limitation, yet also challenges it.