Alnus maritima, commonly known as Seaside Alder, is a deciduous shrub or small tree native to a few disjunct wetland areas in the eastern United States, including riparian zones, swamps, and wet flatwoods. It typically grows to a height and width of 20-30 feet (6-9 meters), forming a rounded canopy. The Seaside Alder has glossy green leaves and catkins that appear before the leaves in early spring. The flowers are not particularly showy, but the small, woody cones persist into winter, providing interest and food for wildlife. Its bark is smooth and gray, becoming slightly fissured with age.

Seaside Alder is valued for its ability to thrive in wet conditions and is often used for streambank stabilization and wetland restoration. It is also suitable for rain gardens and other areas with high moisture levels. This species is relatively low-maintenance, tolerating both full sun and part shade, and prefers soils with poor to moderate drainage. While it is not commonly found in the nursery trade, it can be a unique addition to a native plant garden or naturalized area. Potential problems include susceptibility to alder blight and leaf spot diseases.CC BY-SA 4.0