Phytocaps are soil-plant systems that are installed on top of landfills after closure to achieve hydraulic containment of wastes and rehabilitation of the landform. They provide greater opportunity than other capping technologies to reinstate ecological value, as trees, grasses and shrubs are a core part of the design solution. Despite this, ecological approaches have not been emphasised in landfill rehabilitation. The soil profile of a phytocap is uncompacted and designed to support the vegetation community as well as the proliferation of roots throughout the landfill cap thickness. As phytocaps rely on plant transpiration and evaporation to remove stored water from the designed soil layer, plant selection is a critical factor impacting phytocap success. This paper showcases two Australian phytocap case studies, with a particular focus on plant selection. It outlines a transferable methodology that can be applied to any landfill site context to achieve better design outcomes for phytocaps. This method is based on four pillars. The first pillar is a good understanding and analysis of the constraints of the available soil. The second pillar is a good understanding of the indigenous ecosystems that surround and would have been present at the site prior to disturbance. The third pillar is understanding the current unique site context including differences in environmental conditions that may impact the success of the plant community and any specific compliance requirements that need to be taken into consideration during design. The fourth pillar is understanding the potential benefits that can be achieved beyond pollution abatement and compliance, including ecological, social and community benefits, and how these can be successfully incorporated to create a flourishing ecosystem.