A modular green roof system includes modular panels ( 10 ) providing a surrounded space suitable for supporting live plant growth and adapted for installing onto a roof deck in side-by-side positioning while allowing water flow on the roof thereunder. The panels are filled with growing medium and pre-seeded prior to delivery to the roof site, and delivered in either a preserved condition or a germinated condition. The panels are adapted for interconnecting to adjacent panels, and for connection to an edge finishing/edge termination system ( 46 ) and support structure to enable provision of non-panel areas of the green roof, and above-panel structures.