Purple Moor Grass
(Image credit: Rini Kools)

Purple moor grass (Molinia caerulea) is a true grass native to Eurasia and found in moist, fertile, acidic soil. It has excellent use as an ornamental due to its neat tufting habit and charming, persistent inflorescence. The flowers may soar 5 to 8 feet (1.5 to 2.4 m.) above the basal foliage, producing an architectural appearance that stands out in the garden. Try growing ornamental moor grass in a massed planting for maximum effect.

How to Grow Moor Grass

Ornamental grass lovers should not pass up the opportunity to acquire autumn moor grass. Also, called purple moor grass, this attractive plant has appeal as a single specimen in a combined planter, an accent in the perennial garden or even perched in the rockery. Moor grasses come in many cultivars and are commercially represented by 12 commonly available names. Each has a slightly different foliage trait, height and inflorescence but the basic mounding habit and fine blades recognize them as part of the family. Moor grass is seasonally interesting from summer to winter. The plant is hardy to United States Department of Agriculture zone 4 and adaptable to many types of soils as long as they are moist but well draining. Some partner plants with similar moisture needs to try growing with moor grass are:

  • Epimediums
  • Coreopsis
  • Salix or willow
  • Evergreen ornamental grasses

The plant produces numerous seeds, so remove the seed head in fall to prevent spread. Spread mulch around the grass to a depth of at least 2 inches of good organic material to prevent weed competitors and conserve moisture. Keep mulch away from direct contact with the base of the plant to prevent mold issues.

Moor Grass Care

One of the most important aspects of moor grass care is water. While the plant may rot out in boggy soils, it needs consistent moisture. Water the grass deeply once per week. Overhead watering may promote rust and other fungal diseases, so it is advised to water from the base of the plant. This is a deciduous grass, which will die back in winter. This means there is no need to cut back the plant. In fact, the spent grass is attractive for nesting material to wild birds and helps form a protective nest around the root zone. Simply rake it away in early spring so new blade emergence is not impeded.

Dividing Moor Grass

Division of ornamental grasses is undertaken to prevent center die out, increase vigor, and best of all, to make more of these attractive ornamentals. Moor grass can be divided every 3 to 4 years. The optimum time for division is late winter to very early spring. Dig out around the root zone and deeply into soil to remove the entire plant. Use a root saw to cut it into 2 or 3 sections. Make sure each has plenty of sprouting leaves and a good healthy clump of roots. Plant each section separately. Keep them watered as the plant sprouts and spreads out new roots. This easy step guarantees healthier grasses and increases the number of the regal moor grass.

Bonnie L. Grant

Bonnie Grant is a professional landscaper with a Certification in Urban Gardening. She has been gardening and writing for 15 years. A former professional chef, she has a passion for edible landscaping.