Perennial pepperweed is adapted to sites that are at least seasonally moist in riparian and wetland areas. It is not adapted to upland soils with prolonged drought periods. We do not know what the ultimate range of this species will be. This weed is particularly adapted, but not obligate, to salt affected soils. As such, they are extremely difficult to identify in ruderal communities.
Seedlings are extremely rare in established stands.
The plants form large spreading clones, with new stems arising from the creeping root system. Plants annually die back to the soil surface in the Intermountain Area. We have not studied the phenology of perennial pepperweed infestations in cismontane and coastal California, so our comments on the growth of this weed apply to areas east of the Sierra Nevada. Stems of perennial pepperweed are very woody at the base and persist for several years as dry material, forming nearly impenetrable thickets. Accumulations of old stems often completely obscure the initiation of foliar growth in the spring.