A Graceful addition to shady Gardens
Common Name: Japanese forest grass, hakone grass
Botanical Name: Hakonechloa macra
Form: a soft cascading mound
Plant Type: herbaceous perennial semi-evergreen or deciduous depending on climate
Mature Size: generally 1.00 to 1.50 feet height and width
Hardiness Zone: 5 to 9
Foliage: arching, papery, thin, strap-like leaves, 3 to 6” long and 1/4 to 1/2 inch wide
Flowers: non-showy, tiny, airy clusters of yellowish-green, July, August
Exposure: partial shade is best, tolerates more shade in hot climates
Soil: prefers humus rich, moist and well-drained.
Uses: line paths, foundation plant, massing, mixed border, container plant, shade plant, accent plant, ground cover
Propagation: division of rhizomes
Pruning: cut off old foliage in early spring if it is unsightly
Tolerant: air pollution, black walnuts, deer
Problems: dislikes dry infertile soil and heavy clay soil
Japanese forest grass consist of numerous well-behaved cultivars that may or may not have yellow or cream streaked foliage. Reminiscent of bamboo, its leaves are thin, papery, strap-like and tapered to a point. The many layers of foliage forms a fine-textured and brightly coloured mound. Numerous varieties become tinged with pink, red, orange or purple in fall with the onset of cooler weather. It’s quite a dramatic plant, but in a quiet and calming way. It is a perfect addition to moist shade gardens to add some stylish panache.
Although it is tolerant of shady locations, too much shade causes the foliage to lose their colourful stripes and revert to a lime green. On the other hand too much sun causes the leaves to turn pale and become scorched. It’s best to provide more shade for these temperate plants when grown in sunny and hot climates. Japanese forest grass are ideal perennials for Southwest British Columbia as they prefer cool summers and mild, rainy winters.
Plants grow as clumps from underground rhizomes, but they are not invasive as they are slow growers. Although they are not known for their hardiness they do withstand – 25 degrees Celsius. In cold climates, it’s important to mulch them for the winter. Cover with a few inches of fall leaves, straw or even soil. Don’t remove their leaves in fall as this makes them prone to winterkill. Remove the mulch in early spring when the danger of severe frosts are over and the plant sends out new growth. Cut off the old foliage when the new growth emerges. Place the remnants around the base of the plant as a mulch.
Mulch. Due to Japanese forest grass’ penchant for moist, rich soil, they benefit from an organic mulch. When removing their spent leaves in spring, place their clippings around the base of the plants. Add more organic mulch such as fall leaves and aged wood chips to a depth of 3 inches. For more on mulch click here. Japanese forest grass does not do well in heavy clay soils, nor arid or sandy soils, but no matter what type of soil they are grown in, the do benefit from being mulched.
‘All Gold’: 10-24” x 12-24”, compact, with gold coloured foliage.
‘Aureola’: 12-24’ tall and wide, green leaves with yellow stripes.
‘Beni-Kaze’: 12-18” x 24-36”, green leaves turn to red in fall.
‘Fubuki’: 8-12” x 16–18”, green and white striped foliage turns pink to orange in autumn.
‘Naomi’: 8-16” x 18-24”, green and yellow striped summer foliage that turns red and purple in autumn,
‘Nicolas’: 8-16” x 18-24”, summer green leaves, red and orange fall colour.
‘Stripe It Rich’: 6 to 10” tall x 20”, green with gold stripes.