A grass that was part of the original Midwestern tallgrass prairie, switch grass (Panicum virgatum) is also lovely in the garden.
In July and August, pink-tinged flower panicles rise above the foliage to create a soft, feathery mist. Teardrop-shaped seeds follow in the fall and provide food for songbirds. Its autumn foliage turns soft yellow. Use switch grass as a single vertical accent in a perennial garden or massed in a wildflower or naturalistic garden. In a prairie setting, it's a favored nesting site for pheasants, quail, and grouse.
Common name: Switch grass, prairie switch grass, water panicum
Botanical name: Panicum virgatum
Plant type: Clump-forming, warm-season, perennial grass
Height: 3 to 6 feet
Zones: 5 to 9
Family: Poaceae (grass family)
- Sun: Full sun to part shade
- Soil: Does best in moist sandy or clay soils
- Moisture: Medium to wet is best, but will survive in dry situations
- Mulch: To deter weeds or reduce self-seeding, apply a 2-inch layer of organic mulch around the plants.
- Fertilizer: None required
- Pruning: Cut back clumps to the ground in late winter to early spring before new growth appears.
- ‘Cloud Nine' has blue-green foliage in summer and gold in fall. Reddish-brown plumes appear in late summer. Grows 6 to 8 feet tall in bloom.
- ‘Dallas Blues' has bluish foliage in summer and reddish-purple flower plumes in the fall. It performs well in heat and drought. Grows 5 feet tall in bloom.
- ‘Hänse Herms' has a more compact habit than other cultivars and red-orange fall color. Grows 3 to 5 feet tall in bloom.
- ‘Heavy Metal' has a very upright form with metallic-blue foliage, a white bloom, and burgundy seed heads. Grows 3 to 5 feet tall in bloom.
- ‘Rotstrahlbusch', one of the oldest cultivars, has foliage with a reddish cast all season and brighter red in fall. Slow spreader. Grows 3 to 4 feet tall in bloom.
- In the perennial garden, combine switch grass with tall perennials such as New England aster (Aster novae-angliae) and goat's beard (Aruncus dioicus) for a great fall show.
- Add plumes of switch grass to dried flower arrangements.
- Use switch grass in boggy areas or at the edge of water gardens, ponds, and streams.
- In rich soil or shady spots, switch grass tends to flop rather than stay upright.
- Watch for spikelets that may be sharp.
- Seedlings started from self-seeding will vary from the parent plant.
- Switch grass naturalizes via spreading rhizomes and self-seeding, especially on open soil. It may become aggressive as it gets older.
Pests and diseases
- No serious pests or diseases.
- Sow seed in spring when temperatures are 55ºF to 64ºF.
- Divide in midspring to early summer
- All in the family
- This family is the most important of all plant families because, along with ornamental grasses, it includes lawn grasses and forage grasses for animals; cereals such as rice, corn, rye, barley, sugar cane, and wheat that feed people throughout the world; and bamboo, used in buildings throughout Asia.
Text by Mary Pestel, photo courtesy of Missouri Botanical Garden PlantFinder