Prized for its gracefully arching foliage, Hakone grass, also known as Japanese forest grass, is a tough, low-maintenance ornamental grass that loves moist, shady conditions. This plant forms dense mounds of slender leaves that start solid green, solid golden, or variegated, then change to coppery orange as fall’s cooler weather comes into play. The mounding clumps of grassy leaves gradually slowly increase in size. It is also slow to reappear in the spring so don’t worry if it lags behind other plants in breaking dormancy.
Hakone Grass Overview
Where to Plant Hakone Grass
Pick the planting location according to the type of hakone grass you choose. Varieties with solid green foliage can tolerate sun whereas varieties with golden and variegated leaves (which are the most popular ones) need partial shade. All types should be planted in evenly moist soil with a slightly acidic to neutral pH.
With its cascading mounds of leaves and variety of hues, hakone grass adds graceful texture and bright color to any garden. You can plant it as an accent or a groundcover, around trees, in containers, along paths, or grouped with companion plants. Provide a counterpoint to the elegant lines of the grass with plants that display larger leaves, such as hostas. Hakone cultivars with solid golden leaves or golden streaked with green provide an especially striking backdrop to plants with blue flowers.
How and When to Plant Hakone Grass
The best time to plant is in the spring so the grass has the entire growing season to get established. Dig a hole twice the width of the root ball and with a depth a little less than the height of the root ball. Place the grass in the hole and backfill the hole with soil. Water it well and keep it evenly moist until the grass is established.
Space plants 12 to 24 inches apart depending on the mature size of the variety.
Hakone Grass Care Tips
Light
Hakone grass needs partial shade. In too much sun, especially the types with variegated and golden foliage are susceptible to scorching.
Soil and Water
The soil should be evenly moist, rich in organic matter, well-drained, and with a pH between 6.0 and 7.0.
Water in the absence of rain to keep the soil moist, and mulch around the plant to preserve soil moisture.
Temperature and Humidity
Hakone grass is winter-hardy down to zone 5. Unlike other ornamental grasses, the foliage dies back so it does not provide winter interest. It benefits from a thick layer of mulch to protect the roots.
The grass does well in humid conditions but does not like extreme dry heat.
Fertilizer
Other than a layer of compost, this plant needs no other fertilizer if planted in rich, fertile soil. At the most, you can apply a balanced slow-release fertilizer once in the spring when the new growth starts.
Pruning
The grass does not require pruning other than cutting the dead foliage back to ground level in the later winter or early spring before the new growth starts.
Potting and Repotting Hakone Grass
Because of its small size and slow growth, hakone grass does well in containers. Select a pot with large drainage holes and at least 2 inches larger in diameter than the nursery pot. Fill it with a combination of well-draining potting soil and compost.
Despite the winter-hardiness of hakone grass, in a pot its roots are exposed and subject to freeze-and-thaw cycles. While the grass should definitely remain outdoors during the winter, the roots need protection. You can bury the pot into the ground, insulate it with a thick layer of mulch, or winterize it by placing it in a second, larger pot to create a planting silo.
Pests and Problems
This grass is blissfully unbothered by serious insect or disease problems. Deer don’t like it either.
How to Propagate Hakone Grass
Hakone grass can be propagated by division of the rhizomes in the spring just as the new growth starts. Dig up the entire plant and separate the root it into sections. Make sure each section has signs of new growth. Discard any dead pieces. Replant the sections in a new location at the same depth as the original grass.
Types of Hakone Grass
Golden Japanese Forest Grass
Hakonechloa macra 'Aureola' is a short cultivar (12 to 18 inches at maturity) that brightens gently shaded places in the garden. Its lovely golden-yellow leaves are striped with green and arch gracefully toward the light. Zone 5-9
'All Gold' Japanese Forest Grass
Make a bold statement with this Hakonechloa macra variety. It grows 9 to 14 inches tall and features bright golden-yellow foliage that holds its color throughout the growing season. Zone 5-9
White Striped Hakone Grass
Hakonechloa macra 'Albostriata' is dark green with white stripes of varying thickness. This cultivar tolerates sun better than varieties with golden foliage. It also grows faster and reaches a mature height of 3 feet. Zone 5-9
Hakone Grass Companion Plants
Hosta
Hosta has earned its spot in the hearts of gardeners—it's among the easiest plants to grow, as long as you have some shade and ample rainfall. Hostas vary from tiny plants suitable for troughs or rock gardens to massive 4-foot clumps with heart-shaped leaves almost 2 feet long that can be puckered, wavy-edged, white or green variegated, blue-gray, chartreuse, emerald-edged—the variations are virtually endless.
Holly Fern
For that shady spot, you can't go wrong with holly ferns. Their evergreen fronds always look good and they mix well with other shade lovers, without taking over. They can be planted close and massed as a groundcover, or used as accent plants where soil is rich and well-drained.
Columbine
Perfect for cottage and woodland gardens, old-fashioned columbines are available in almost all colors of the rainbow. Intricate little flowers, they are most commonly a combination of red, peach, and yellow but also blues, whites, pure yellows, and pinks; they look almost like folded paper lanterns. Columbine thrives in sun or partial shade in moist, well-drained soil. Plants tend to be short-lived but self-seed readily, often creating natural hybrids with other nearby columbines.
Frequently Asked Questions
- Is hakone grass invasive?Even though it is a creeper, spreading by underground rhizomes, it is not invasive.
Even though it is a creeper, spreading by underground rhizomes, it is not invasive.
- Can you grow hakone grass from seed?Potentially yes, but the seeds are not widely available. Seeds from one of the popular cultivars won’t produce a grass that is true to the parent.
Potentially yes, but the seeds are not widely available. Seeds from one of the popular cultivars won’t produce a grass that is true to the parent.