Difference Between Sea Oats & Pampas Grass

Appearance

• The biggest single difference between sea oats and pampas grass of importance to gardeners is their size. Pampas grass is one of the tallest ornamental grasses -- the flower stalks reach up to 10 feet tall and the foliage in commonly 6 feet tall and wide. The flower stalks of sea oats are also impressively tall, rising from 5 to 8 feet above the foliage, but the bulk of the plant stays much lower, at around 2 feet tall. Both are evergreen, clumping grasses, but sea oats form a loose, airy clump compared with the dense, impenetrable mass of pampas grass.

Origin and Climate

• Sea oats are native to the Gulf Coast and southern Atlantic seaboard from North Carolina to southern Florida, though they are now considered an endangered species in the wild. They grow well throughout their native range, as well as other mild climates along the Atlantic and Pacific coasts. Pampas grass is from South America and is adapted to almost every climatic region of the United States, except where winter temperatures dip below 15 degrees. Sea oats have very specific adaptations to coastal conditions and are not typically planted in inland gardens, while pampas grass is equally at home near the ocean or inland.

Growing Conditions

• Sea oats are universally adapted to coastal growing conditions -- full sun, sandy soils, high winds and salt spray. Pampas grass is adapted to these conditions and more, growing in heavy clays and partial shade as well. Neither species is bothered by any significant pests or disease, and both are drought-tolerant and thrive in soils of low fertility. Because sea oats are so finely tuned to their native soil, fertilizer is not recommended. Pampas grass responds well to applications of nitrogen fertilizer, growing bigger and faster than without.

Landscape Applications

• Sea oats are important as a species for native gardens and coastal restoration projects, performing the critical function of dune stabilization and erosion control. As an ornamental, they are hard to match in seaside landscapes, especially when used in a naturalized setting. Pampas grass is also a good choice for erosion control on the coast or elsewhere and makes an effective windbreak. The giant specimens can be used as a focal point in the landscape, but are better in clumps of three or more or used as a tall backdrop for a perennial bed. Pampas grass is considered an invasive species in some areas, including coastal California.