Transplanting seagrasses can help restore ecologically important and threatened marine ecosystems. Based on the L-system formalism, Renton et al. present a functional–structural plant model of seagrass growth that integrates data collected from short-term trials and experiments for Posidonia australis. They use the model to conduct an evaluation of different transplanting strategies and find that reasonable long-term outcomes can be predicted, based only on short-term data. Marine restoration represents a novel application of functional–structural plant modelling.