Seagrasses are habitat-forming organisms providing key ecosystem services in coastal marine environments, including carbon sequestration, habitat provision, and water clarification. Anthropic pressures on coastal areas are major drivers of global seagrass regression. In the Mediterranean Sea, Posidonia oceanica meadows have experienced a documented decline over the past century. Therefore, restoration and conservation initiatives are increasing, exploring several techniques. Among these, seed-based restoration has emerged as an effective and sustainable approach, as the use of sexual propagules provides ecological genetic, and evolutionary advantages to the restored populations. Furthermore, the ability to propagate plants in controlled cultivation systems can significantly increase the yield of the biological material collected in the field, reducing potential negative impacts to donor beds. Here we evaluate the feasibility of a novel P. oceanica transplantation techniques that makes use of nursery propagated plants from seeds and takes advantage of specific adaptive traits of P. oceanica juveniles, namely adhesive root hairs, to achieve fast and secure anchorage to specially designed supports. These supports act as stabilizers during seagrass early life stages. P. oceanica beach-cast seeds were collected along the northwestern coast of Sicily and grown in two mesocosms located in Genoa (Liguria) and Mazara del Vallo (Sicily), using rocky supports designed to maximize adhesion rate and strength. Half of the seedlings were cultivated for six and the other half for eleven months in order to test two transplanting periods: winter and spring. After six months of ex situ cultivation under controlled conditions, seedling survival reached 75% and approximately 95% of the plants spontaneously attached to the rocky supports, as observed also after eleven months. Plantlets, together with their supports, were transplanted at the selected restoration site on dead matte. After four months, in situ early survival reached 96.8% during the winter season. The experiment is still ongoing.