“Which plants should I grow, and how many?” The IMLS National Leadership Project, Safeguarding our Tree Collections, seeks to answer this fundamental question. Through structured comparisons of genetic data among major groups of seed plants, management recommendations and their broadness can be determined. Results show that careful consideration of the target species is essential when planning for collections management; i.e. biology informs strategy. The application of novel zoo management software to our plant data allows management of “metacollections” at separate gardens. Integrating precise ex situ conservation assessment with in situ management, monitoring, and community outreach can “close the loop,” ensuring our living treasures do not go extinct.