Hakonechloa

( hah - koh - neh - KLOH - ah )

At-A-Glance Information

Commonly called Japanese Forest Grass or Hakone Grass, this genus of perennial grasses includes species which need full sun and regular water to perform well in the garden. These lush, mounding grasses reaches up to 1 to 3 feet tall and a little wider, spreading slowly via underground runners. Leaves turn copper-orange in fall before being shed. Use Hakone Grass as a groundcover, path border, container plant, or on sloped areas. They are used in Japanese gardens, woodland landscapes, and also fill in spaces in tropical gardens.

Hakonechloa Cultivars and Varietals

The genus Hakonechloa includes just one species, Hakonechloa macra, and is a member of the plant family Poaceae. It is closely related to the genus Molinia. The best growing zones for Japanese Forest Grass are USDA hardiness zones 5-9 or Sunset growing zones 2b-9, and 14-24. To find your zone, click here: Zone Map.

'Albostriata'
With creamy white and green striped foliage to 12-18 in. tall.

'All Gold'
To 14 inches tall and 18 inches wide with golden yellow leaves.

'Aureola'
With gold foliage variegated with lime green stripes. To 12-18 in. tall and 18-24 in. wide.

'Beni-kaze'
Bright green leaves transition to deep red, burgundy and gold in fall.

'Fubuki'
To 14-18 inches tall and wide with white and green leaves.

'Lemon Zest'
Chertreuse-yellow foliage is striped with creamy white.

'Stripe it Rich'
With light green foliage with a wide central band of cream.

Caring for Hakonechloa

Plant Hakonechloa, or Japanese Forest Grass, in a space in the landscape that receives partial shade to dappled shade; ideally, they appreciate between 4 and 6 hours of sun, primarily in the morning hours. In warm, inland climates or drought conditions, they prefer full shade. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.0 and 7.0 (slightly acidic to neutral). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants perform well in consistently moist soils. As a general rule of thumb, water whenever the top inch or so of soil feels dry to the touch.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season. In fall, leaves will turn bright colors and fall from the plant. Naked stems can be trimmed back in late winter to early springtime in preparation for a new flush of growth. Hakone Grass will need to be divided every few years; for instructions on how to divide these grasses, see the Propagation section below. It can survive in the garden for between 5 and 20 years depending on the growing conditions. They take two or three years to reach full size, and will form clumps over time.

Caring for Hakonechloa in Containers
Japanese Forest Grasses are wonderful in the ground but can also be grown in containers, providing lush foliage to balconies and patios. Choose a container that is at least a few inches wider and deeper than the nursery pot or root ball. Ensure that the pot has adequate drainage holes on the bottom to allow for excess water to flow away. Fill with a well-draining potting mix amended with organic material and perlite, and top with a layer of mulch to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly as the plant establishes itself in its new home. Once established, waterings can be lessened. These plants, when grown in containers, will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top few inches of soil feels dry to the touch. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Every few years, check the bottom of the pot to ensure that the plant is not outgrowing its root space. If roots are growing through the drainage holes in the bottom of the container, it is a good indication that it needs to be potted up; choose a slightly larger container and repot. Hakone grass will also need to be divided every few years; for instructions on how to divide these grasses, see the Propagation section below.

Propagation

Hakonechloa, or Japanese Forest Grass, is best propagated by division or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate Japanese Forest Grass, follow the instructions below:

Propagating Hakonechloa by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, and a spray bottle. If you don't have any potting medium on hand, you can make some. A good potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
Harvest your seeds. The seed heads on plants are pretty easy to spot, and are typically held amongst the foliage on thin stems. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Get your container prepared. Water the seed tray or pot filled with soil, and ensure that good drainage is occurring. Place the seeds about a quarter inch under the soil surface. Cover them with soil and water with the spray bottle. Place the tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2-6 weeks from sowing.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Hakonechloa by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil, compost and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in early spring or fall. To propagate by division, follow these steps:

Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the root(s). Once you have worked it up out of the ground, lay it out.
Separate the removed patch of grass into sections using a sharp, clean knife or trowel. Ensure that each division has a healthy root system and a few shoots. Any dried out areas with dead roots can be tossed in the compost.
Prepare your pot(s) or new planting site(s) with well-draining soil and compost and rake it in. Water thoroughly, and then place divisions on top.
Keep soil consistently moist as the newly-planted divisions establish strong root systems in their new home. Provide regular waterings, especially during dry spells. It typically takes between 1 and 2 weeks for these grasses to develop their initial shallow root systems, and up to 30-45 days for their deeper roots to form.