Plant library · Ornamental Grasses
Pennisetum setaceum
Purple Fountain Grass forms an arching clump about 3½ feet tall and 2½ feet wide, with fuzzy purple plumes from summer into fall. Its upright base and outward-curving foliage give it a strong vertical presence without reading as a solid screen. Use it where a single clump can punctuate a planting or repeat it at measured intervals for a more rhythmic edge.
Place Purple Fountain Grass behind low edging plants, near the middle or back of a sunny border, where its plumes can rise above neighboring foliage. It also works as a focal plant in a large container, especially beside an entry, patio, or seating area. Keep the arching leaves out of narrow paths and allow enough clearance for their seasonal sweep rather than planting directly at the paving edge.
Set plants 2½ feet apart, center to center, matching the expected mature width. In a row, this creates a nearly continuous sequence of clumps; widen the intervals slightly when each plant needs to read as a separate accent. Reserve a footprint at least 2½ feet across for each clump, plus extra open space on the side facing a path, door, or container grouping.
Use this grass in full sun, placing it with other lower-water plants rather than in the most regularly irrigated part of the garden. A bright, open position also keeps the foliage and plumes visually distinct from surrounding planting. Avoid relying on it to fill a shaded gap.
Purple plumes carry the display from summer through fall, so leave its allotted space open for late-season interest rather than crowding it with plants that peak earlier. Although perennial in USDA Zones 8 through 11, it is annual in most other zones. Plan annual plantings as a season-long feature that will leave a vacancy after frost.
This species can self-seed and is considered invasive in some areas. Before repeating it through a large bed or near open ground, check local guidance and choose a placement where seedlings can be noticed and removed easily. Containers and contained planting areas offer a more controlled way to use its fountain-shaped form.[1][2]
Editorial content updated 2026-07-20.