Japanese forest grass- Hakone grass

Japanese forest grass- Hakone grass (Hakonechloa macra)

By Kim Willis These articles are copyrighted and may not be copied or used without the permission of the author.

If you like ornamental grasses but thought you couldn’t grow them in your shady garden Japanese forest grass may be just the plant for you.  This lovely arching grass is native to Japans cool Hakone mountain area and will grow in partial or even full shade.  It’s hardy in planting zones 5-9 but probably does best in zones 5-6 where summers tend to be a bit cooler.  In zones 7 and above it will need to be in shadier locations.  Hakone grass provides interesting texture in shade gardens that tend to feature broad leaved plants.

Hakone grass has narrow leaves that arch.  It’s a deciduous perennial, dying to the ground each winter.  Plants grow to about 18 inches high and wide.  It has rhizomous roots that slowly spread and create larger clumps.   The species has medium green leaves.  The most common variety sold is probably  ‘Aureola’ which has a golden stripe highlighting blade edges. ‘All Gold’ is a variety which has almost totally golden leaves.  In deep shade it becomes more chartreuse. ‘Albo-striata’ is hard to find but it’s a forest grass with white variegation.  ‘Red Wind’ is a variety that takes on a reddish cast in fall and ‘Nicolas’ is similar but with a more purplish fall color.

Hakone grass does flower but like most grass flowers they are not that showy and are generally hidden among the grass blades.   You could collect the seeds but Hakone grass is slow growing from seed and new plants are better obtained by dividing large plants in early spring.

Hakone grass will grow in partial or full shade but tends to scorch in full sun.    In zones 5-6 partial or light shade brings out the best color and growth while in warmer zones the plant requires more shade and moisture to do well.  They prefer loose well drained soil that is kept evenly moist.  Fertilizer probably isn’t needed, but a grass fertilizer might give poorly growing plants a boost.  Make sure plants are regularly watered while they are getting established.

Hakone grass will grow in the root zone of black walnut trees and is said to be deer resistant.  Rabbits will eat it however.  Insect or disease problems are rare.  In the late fall or early spring before new growth starts the previous year’s leaves should be cut back to the ground.  Some varieties have interesting fall color but most just turn straw brown.  In zones 5-6, winter mulch is helpful, especially in exposed areas.  I have found leaving the foliage alone until late spring allows the plant to provide its own mulch.

Hakone grass can also be used to provide texture and interest in large containers.  They can be used to line paths or woven among plants like hosta, heuchera, astilbe and ferns. They can be used as a clumping ground cover beneath trees.  The golden colored varieties looked nice mixed with purple foliaged plants like heuchera or Japanese maples.  If you have a shady patch lighten it up with some Hakone grass.