This dataset was collected in support of a study on the resilience of restored seagrass (Zostera marina) meadows to marine heatwave exposure in North Wales, United Kingdom (Thomas et al., 2026). It provides plot-level planting records for seagrass planted at four intertidal sites along the Llŷn Peninsula and Ynys Môn between February 2023 and March 2024, including planting method (directly injected seeds, hessian bags, and seed balls), planting date, number of seeds, seed balls and hessian bags planted per plot, and dGPS-surveyed plot coordinates.