Cortaderia selloana
Common Name: Uruguayan pampas grass 
Type: Ornamental grass
Family: Poaceae
Native Range: Temperate South America
Zone: 8 to 10
Height: 8.00 to 12.00 feet
Spread: 4.00 to 6.00 feet
Bloom Time: August to February
Bloom Description: Silver white
Sun: Full sun
Water: Dry to medium
Maintenance: Medium
Suggested Use: Naturalize
Flower: Showy, Good Cut, Good Dried
Tolerate: Drought, Black Walnut, Air Pollution

Culture

Winter hardy to USDA Zones 8-10 where it is best grown in dry to medium moisture, well-drained soils in full sun. Tolerates light shade. Tolerates drought once established. Cut foliage back to the ground in late winter. Clumps may be divided in late winter to early spring. This grass is technically gynodioecious, but usually appears dioecious. Female plants produce prodigious amounts of seed and can self-seed freely, often resulting in naturalization that displaces valuable native plants. This plant is considerably invasive in certain areas of the western U. S., particularly California and Hawaii where it is not now recommended for planting. In the St. Louis area (USDA Zone 6), this grass will generally not survive winter, and should be planted in large containers (e.g., whiskey barrels) for overwintering in a greenhouse.

Noteworthy Characteristics

Cortaderia selloana, commonly called pampas grass, is native to Brazil, Argentina and Chile. Its common name is in obvious reference to the Argentine grasslands (the pampas) where it grows. It was planted around the world in Victorian times, and today is considered to be one of the most popular of the ornamental grasses. This is a tough, large grass that forms dense, substantial clumps (tussocks) featuring arching, serrulate, narrow green leaves that are topped in fall by huge, feathery, silvery white plumes. It was first introduced into the U. S. in 1848, and for many years now has been grown as an ornamental plant in certain southern and western parts of the U.S. It has also been grown commercially for harvest of its large flower plumes for use in dried arrangements. Leaf blades are extremely sharp (easily cut human skin) and may reach 6-8’ in length. Flower plumes (1-3’ long) may rise to 10-12’ tall on erect stems. Silvery white plumes (sometimes with traces of pink) are more impressive on female plants than on male plants.

Genus name comes from the Argentinian name.

Problems

No serious insect or disease problems. Invasively self-seeds in some warm winter areas. Leaf edges are extremely sharp.

Garden Uses

Where winter hardy, this is a large ornamental grass for large landscapes. Excellent specimen. Background plant for borders. Screen. Plumes may be cut and dried for use in indoor flower arrangements. Best grown in containers in the St. Louis area.