Pampas grass is an attractive and hardy ornamental grass which is nearly trouble-free once well established. It grows in clumps which grow 8 to 10 feet high and wide. Its most distinctive feature is the silver-white to pinkish feathery plumes which appear in the summer and last until autumn. These plumes are popular in dried arrangements and other interior decor.
Pampas grass grows best in well-drained soil in partial shade to full sun, and thrives in USDA hardiness zones 5B through 11. In shady areas, it will grow slowly and plumes are less likely to develop. Because of its height, pampas grass makes a good barrier or windbreak plant in large yards or along highways. It is tolerant of salt spray, making it a good choice for planting in coastal areas.
Use care when choosing a location for your pampas grass planting; its sharp, serrated leaves can cause painful cuts to people walking past.
If you're planting pampas grass in your yard for the first time, you can plant seeds. Seedlings vary greatly in flowering period, growth habit, and the size and shape of plumes, so to keep a uniform display, propagate new plants by dividing existing clumps. Divide the clump by first cutting the leaves down to 4 to 6 inches above the crown, then digging the plant up and removing it from the ground. Cut the clump into divisions, remove any dead or diseased material from each, and replant them. Leave plenty of space between plants; remember, pampas grass produces large clumps which can take up to three years to reach full size.
In the early spring, before growing starts, prune to remove any dead material from your pampas grass. In the northern part of the growing range, this may involve cutting the whole plant down to 4 inches above the ground. Wear gloves, long sleeves, and long pants when pruning pampas grass to avoid cuts from the leaves.
When your pampas grass is a few years old, you may notice that all new growth occurs at the sides of the clump and the center remains bare. This is caused by too much of the old, woody growth choking out new growth, and it's time to divide the clump and replant.
To promote growth and production of plumes, fertilize your pampas grass with a complete fertilizer four times a year. If you live in the northern reaches of the growing zone and your winters are cold, mulch heavily in the fall to prevent root damage from freezing.