Reed grass is an attractive perennial with arching green foliage and heads of purple-bronze seeds from mid- to late summer.


Plant facts

  • Common name: Reed grass
  • Botanical name: Calamagrostis x acutiflora
  • Zones: 5 to 9
  • Size: To 6 feet tall
  • From: Areas of Europe and Asia
  • Family: Poaceae (grass family)


Growing conditions

  • Sun: Full sun
  • Soil: Well-drained soil is best, but the plants tolerate a range of soil conditions.
  • Moisture: Drought and moisture tolerant.


Care

  • Mulch: A layer of mulch reduces competition from weeds and conserves soil moisture. Organic mulches add to the soil's structure over time.
  • Pruning: If desired, leave stems and plumes standing in the garden for winter interest. Cut back plants to the ground in spring before growth begins.
  • Fertilizer: In most soils, the plants require no fertilizer. In very poor soils, use an all-purpose garden fertilizer in spring.

Propagation

  • Division: Divide clumps in spring or autumn. For older clumps, you may need to use an axe, saw, or spade to cut them apart.

Pests

  • Fungal diseases: To deter diseases, prune the plants to encourage good air flow, avoid wetting the foliage, and mulch the soil around the plants.
  • Leaf spot: In summer or autumn, the leaves develop yellow or dark-colored spots with concentric rings around them, forming a bull's-eye pattern.
  • Powdery mildew: This disease appears in mid- to late summer. A grayish powder covers the leaves and causes them to drop off.
  • Rust: (especially cedar-apple rust) Leaves develop spots and small masses of rusty powder. Infected leaves die by the end of the season.

Garden note

  • In particularly rich soil, reed grass spreads quickly, even though it's not usually considered invasive or especially aggressive. In fertile soils, give the grass plenty of room to spread.


Selections

  • Calamagrostis x acutiflora ‘Avalanche': Grows to 5 feet tall. Green blades have white stripes down the centers. Light purple plumes in early summer turn golden brown in late summer. Zones 5 to 9.
  • Calamagrostis x acutiflora ‘Karl Foerster': Grows to 6 feet tall with green leaves and bronze-purple flower heads. Zones 5 to 9. Named a Perennial Plant of the Year by the Perennial Plant Association.
  • Calamagrostis x acutiflora ‘Overdam': Grows to 5 feet tall with green leaves with yellow stripes and brown-purple flower heads. Zones 5 to 9.
  • Calamagrostis x acutiflora ‘Stricta': Grows to 6 feet tall with green leaves and bronze-purple flower heads. Blooms a bit later than other selections. Zones 5 to 9.