AbstractExperimental plots of pulverized fuel ash (PFA), alone or mixed with flue gas desulphurization (FGD) gypsum, were seeded with topsoil from areas where PFA had been revegetated naturally, or with estuarine soil. Plots containing fresh PFA became more saline during the first three years due to formation of a salt crust, and these plots experienced colonization by halophytic species. Plots initially containing 2‐year‐old PFA declined in salinity throughout the experiment and were colonized by a richer plant community dominated by legumes. A total of 57 plant species was recorded in the two experiments. Of these,Melilotus officinalis(ribbed melilot),Medicago lupulina (black medick), Vulpia myuros(rat's tail fescue), andPuccinellia maritima(common saltmarsh grass) showed commercial potential for stabilizing these wastes, and by implication other saline or high‐boron mate