Ornamental grass is one of several desert plants that I recommend for people who want desert plants that are perennial (you need to plant them only once), hardy, low care, relatively drought resistant, easy to find, and pretty cheap to buy--this is the only one on my list that doesn't have colorful flowers, but they do have blooms, usually feathery.
Ornamental grasses are large, evergreen plants. They are fast growers that thrive in the desert heat, and when they flower there will be long stalks with plumes that rise up from the plant. Ornamental grasses here are not picky about soil and can take the full desert sun. You won't see ornamental grass on many lists of recommended desert garden shrubs, but I like it! It isn't dirty, and it's got a great soft, desert look to it. Ornamental grass makes a nice barrier, so it can be planted around a spa or can be used to take up a big corner space.
Ornamental grass doesn't require much care, but it does need a haircut now and then. Remember, ornamental grasses grow to be large, so make sure you have the space to let them spread out.
One of the most common landscape grasses sold in the Phoenix area is Fountain Grass or (Pennisetum setaceum), pictured here. While it is pretty, it is considered an invasive plant, displacing native grasses, spreading rapidly, fueling fires, and is changing the natural landscape of the Sonoran Desert in a negative way.
More Easy Desert Plants