<p>Early childhood is the time when children are eager to discover nature as they spontaneously learn from their surrounding environments, and plant-based loose parts are a great fit to meet such curiosity of young children. Although loose parts play has long been researched, child-friendly planting design to promote plant-based natural loose parts in outdoor learning environments is an under-researched area. Moreover, a child-friendly planting design requires an appropriate plant database. Keeping loose parts play as the primary focus of the design, this research attempted to expand our understanding of how different plant parts may add play value to a learning landscape for children by adding loose parts play affordances. In this research, several plant databases were examined thoroughly to investigate whether they offer any data on the play value of plants for children. GIS-based behavior mapping data and video data on plant-based play and children's interactions in a naturalized preschool outdoor environment have been analyzed to identify plants used and to understand how children use plant-based loose parts in a ‘real world’ setting. Comparing empirical data of loose part play affordances of different plants with the play value assumptions found in the databases and based on a case study, this research attempted to develop a ‘playful’ planting palette appropriate for the semi-arid climate zone of Texas. The planting palette was developed based on the literature and expert opinion and aims to maximize the amount and supply of natural plant-based loose parts on the site year-round.</p>