When to Cut Back Miscanthus Grass

Miscanthus is a large ornamental grass that may grow from 6 to 12 feet in height. The grass performs best in rich, moist soils with full sun to partial shade. Miscanthus will stay erect through most of the winter, but the foliage becomes dry and damaged toward the end of the season. Foliage is attractive and affords some protection for the crown, but should be cut back at the end of winter or in very early spring.

Miscanthus is a perennial favorite in the landscape for three seasons of interest and an architectural aspect. The grass is a clumping form and will not become invasive. Miscanthus ornamental grass produces a soft feathery inflorescence and turns golden or bronze in fall. There are many varieties common to garden use from slender Japanese silver grass to speckled porcupine grass. The colors, lengths and widths of the blades are extremely varied, and there is a Miscanthus for almost every garden.

Miscanthus may be used in United States Department of Agriculture zones 4 to 9. It is a wild grass in most parts of Asia and is suited to temperate and humid heat climates. It is ideal perched along a water feature or as part of a perennial border. Some of the varieties will get extremely tall and are useful as borders. Plant the grasses close to each other as a wild and fascinating hedges. The Miscanthus does well in well-drained containers and as specimen plantings in sunny locations.

Miscanthus should be allowed to retain its foliage over winter as protection for the crown. It will fade and dry out, but actually makes an attractive specimen in the garden. In January or February, the foliage will start to peel and become messy. You can cut it back at that time or wait until very early spring. Grass shears are an easy way to prune Miscanthus. Tie the foliage together at the top like a ponytail, and then cut across the base of the plant at a level of 6 to 10 inches. Make a slightly domed shape to preserve the grass that is beginning to come up at the center of the plant.

Most perennial plants need division every two to three years, and Miscanthus is no exception. The plant will get floppy and the production of new blades in the center will diminish if you don't divide the plant. Division is best done in spring as early as soils are workable. Dig up the plant and cut it into two to four sections. Ensure each section has a thick batch of roots and is beginning to crown with many new, green grass sprouts. Plant the sections as new plants, and each will fill in over the season.