San Diego, CA Invasive Plant Rules: Prohibited Species (2026)

San Diego has several regulatory frameworks addressing invasive plants. The San Diego Municipal Code prohibits invasive non-native species adjacent to open space areas. The city maintains a Prohibition Plants and Substitutions list identifying plants that should not be used in landscaping near natural areas. The California Invasive Plant Council (Cal-IPC) classifies invasive plants by severity (High, Moderate, Limited), and species on the High list include giant reed (Arundo donax), pampas grass (Cortaderia selloana and C. jubata), iceplant (Carpobrotus edulis), Mexican fan palm (Washingtonia robusta in natural areas), and fountain grass (Pennisetum setaceum). The San Diego County Invasive Ornamental Plant Guide created by ASLA-SD and CNPS San Diego provides region-specific guidance on invasive ornamentals. The city's Water Efficient Landscape Ordinance (SDMC §142.0403) mandates water-efficient landscaping for new construction and major renovations, encouraging native and climate-adapted species. The Brush Management Regulations require removal of flammable non-native vegetation in fire hazard zones.