Content Detail

Japanese silver grass is also referred to as giant miscanthus to separate it from the smaller species of miscanthus that is commonly found in gardens. Giant miscanthus can grow up to 14 feet tall and can be overwhelming in smaller gardens.  It is a warm season, clumping grass, which is borderline hardy in zone 5.

  • 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)
  • Hardiness zones Zone 5 (Chicago), Zone 6, Zone 7, Zone 8, Zone 9
  • Soil preference Moist, well-drained soil, Wet soil
  • Tolerances Clay soil, Dry sites, Occasional drought, Wet sites
  • Season of interest early fall, early summer, early winter, late fall, late summer, mid fall, midsummer, midwinter
  • Flower color and fragrance Other
  • Shape or form Arching, Upright

Size and Form:

This grass can grow as tall as 14 feet in one season.  It has an upright to arching habit.  It is considered a clumping grass, although it does spread slightly by rhizomes.

Native geographic location and habitat:

It is native to Japan and Taiwan and is commonly found in lowland areas.

Leaf description:

The leaves are up to 1 1/2 inches wide and 1 to 3 feet long. They are medium green with a very distinct white midvein. Leaves turn beige in autumn and often fall off in winter, leaving bare stalks.

Flower description:

Flowering time is late summer into early autumn (usually August to September). The tiny flowers are held in tassel-like clusters that are held above the foliage. The clusters are pinkish silver on emergence. Flowering may not occur in colder climates.

Fruit description:

The small fruit (caryopsis or grains) form along the tassel-like structures that held the flowers.  The fruiting structure takes on a silvery color for winter.

Plant care:

This grass tolerates a range of soil moisture from well-drained to wet. It does  best in full sun. Too much shade can lead this tall grass to become floppy. This is a warm season grass, so its most active growth occurs in summer.  It will remain standing through the  winter and can act as winter interest.  It is common for the leaves of this grass to fall away in winter, leaving only the upright stems.  Since this grass remains attractive through winter, it should not be cut back until early spring, before new growth begins.  At that time, it can be cut down to the ground.

List of pests, diseases, and tolerances:

Miscanthus mealybug is a possible pest.

 

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