Content Detail

Purple moor grass is similar to moor grass but is taller, in some cases significantly taller. For many cultivars, the flowering stalks make up most of the height, with the mound of foliage often only 2 to 3 feet tall.

  • Family (English) Grass
  • Family (botanic) Poaceae
  • Tree or plant type Grass, Perennial
  • Native locale Non-native
  • Size range Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Acid soil, Moist, well-drained soil, Wet soil
  • Tolerances Alkaline soil, clay soil, Wet sites
  • Season of interest early winter, late spring, early summer, midsummer, late summer, early fall, mid fall, late fall
  • Shape or form Arching, Upright

Size and Form:

The foliage of this grass forms a 2 to 3 feet tall mound. In flower, the plant may be 8 feet tall (depending on cultivar), with a more arching habit.

Native geographic location and habitat: 

Native to the British Isles, Europe and Asia. It is common in moist to wet areas.

Leaf description: 

Leaves are up to 1/2 inch wide and 18 inches long. Green in summer, they change to yellow in fall.

Flower description: 

Flowering occurs in mid-summer. The tiny flowers are held above the foliage in spikes atop stalks that may be 3 to 5 feet tall (depending on cultivars). The flowers are wind-pollinated.

Fruit description: 

The small fruit (caryopsis or grains) form along the spikes that held the flowers. They persist into fall, but will eventually break off during fall and winter.

Plant care:

Purple moor grass achieves its best growth in moist sites with full sun. In hot climates, flowering will be better if the plant is in light shade during the heat of the day. Avoid dry sites.  This is a warm season grass, so its most active growth occurs in summer. It will remain standing for at least part of the growing season. Unlike other warm season grasses, the leaves and flower stalks will break off on their own in late fall and early winter.

List of pests, diseases, and tolerances: 

No serious problems.

Bergfreund (Mountain Friend) purple moor grass (Molinia caerulea ssp. arundinacea ‘Bergfreund’):

Foliage is 3 feet tall, with the flower stalks rising 4 to 5 feet tall.


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