The habitat conditions in short rotation coppice (SRC) differ from the conditions found on grassland and arable land with respect to herbicide and fertiliser input, disturbance frequency, radiation regime and nutrient cycling. Based on soil chemical analyses and radiation transmission measurements, habitat conditions in 10 SRC plantations (poplar and willow) of different stand ages were characterised. Vegetation surveys were conducted to evaluate the potential contribution of SRC to the conservation of farmland plant diversity. Light availability decreased strongly with time since planting, which was the main driver of a large decrease in plant diversity. Community composition shifted from pioneer vegetation dominated by a wide range of annual archaeophytes to communities composed of a few generalist perennial species. No red list plant species were found. SRC can have either a beneficial or a detrimental effect on the plant species richness of agricultural landscapes, depending on the type of land use being replaced and the management intensity of the SRC. The changes to habitats are such that SRC should not be established on marginal arable land where high agri‐biodiversity usually still exists.