Ornamental plant nurseries in Mexico are frequently affected by Phytophthora pathogens that cause rotting, wilting, and dieback in flowers and ornamental plants. This study identified seven different Phytophthora species infecting 13 types of ornamental plants in Mexican nurseries, including two species never before reported as hosts for the pathogen anywhere in the world. The diversity of plants grown together in nurseries increases the likelihood that the pathogen will spread to new host plants and escape to home gardens and natural ecosystems.