Japanese red blood grass

Care Of Japanese Blood Grass: Tips For Growing Japanese Blood Grasses

Ornamental grasses provide explosions of movement and texture to the landscape. The Japanese blood grass plant adds color to that list of attributes. It is an excellent border, container or massed plant with red tipped foliage and easy maintenance. There are no real tips on how to grow Japanese blood grass, but it is not hardy in freezing temperatures. Care of Japanese blood grass is novice level and an excellent starter plant for undermanaged garden beds.

USDA plant hardiness zones 5 to 9 are best suited for growing Japanese blood grass. Try using this ornamental as a specimen in a fabulous pot or in groups along a path to produce a sweeping effect of crimson and green.

What is Japanese Blood Grass?

Japanese blood grass (Imperata cylindrica) is a perennial plant. Its foliage begins green with slightly tinged red tips and matures to the blood red color for which it is known. The plants get only about 2 feet (.6 m.) in height and are clumping rather than spreading grasses.

They have little invasive potential when they are in their

cultivated form, but if the plants are allowed to revert to green, they can become a nuisance plant. In fact, half the states in the United States have banned the sale and planting of the grass because it spreads through its rhizomes and takes over areas of native flora. The green is more aggressive than the cultivated red form.

How to Grow Japanese Blood Grass

The Japanese blood grass plant is low maintenance and has few pests or problems. The biggest issue is when the plant is not sited correctly. It prefers cool, moist locations and tends to revert in full shade, which makes it a potential hazard to native plants. Gardeners that are growing Japanese blood grass in southern states may find it weedy.

When the plant is too wet, however, the roots can get a variety of rots. Amend your garden soil with some gritty material and compost and check the drainage before you install this grass.

It is tolerant of urban pollution and drought-resistant once established. For color and persistence, the Japanese blood grass plant is an ideal candidate for most cultivated gardens.

Care of Japanese Blood Grass

The better the sun exposure, the truer and deeper the red color becomes in this spectacular ornamental grass. Established plants can withstand low moisture situations, but for the best appearance, water once weekly. Water plants in containers at least once per week in summer but reduce watering in winter as the plant goes dormant.

Division is the quickest and most reliable method of propagating this plant.

As long as the Japanese blood grass plant is installed in well-draining soil, few problems exist. However, those in clay soils tend to have wet roots, which promote root rots and fungus. The blades of the grass may get eaten by snails and slugs and can also get rust disease, which disfigures the leaves. Avoid overhead watering and use an organic slug bait to keep the brilliantly colored foliage free of holes and damage.

Red Baron Japanese blood grass

Size and Form

‘Red Baron’ Japanese blood grass has an upright habit and grows 1 to 2 feet tall. It is a running grass that spreads by rhizomes, but it generally spreads slowly.

Plant Care

Best growth is obtained in full sun and a moist, well-drained soil. The plant will grow in light shade but the red color will be diminished.
‘Red Baron’ can revert back to the species and then can become invasive. ‘Red Baron’ shows some shade of red on its leaves at all seasons. Any plant that changes to green should considered a reversion to species and should be removed and destroyed.

This is a cool season grass, so its most active growth occurs in spring and fall. It will be semi-evergreen in winter and can act as winter interest.

Since this grass remains semi-evergreen 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 if needed or simply trimmed to remove winter damage.

Disease, pests, and problems

No serious pest problems.
Any plant that changes to green should considered a reversion to the invasive species and should be removed and destroyed.

Native geographic location and habitat

Native to Japan.

Leaf description

The narrow leaves will grow 1 to 1 1/2 feet tall. When they emerge in spring, the green leaves will be tipped with red. As the season progresses, the color spreads through the leaf and it deepens. By fall the leaves are blood red. In winter, as the plant goes dormant, the leaves will turn a coppery color.

Flower description

‘Red Baron’ seldom flowers. When the plant does flower, the tiny flowers are held in a spike.

Fruit description

The small fruit (caryopsis or grains) form along the spike that held the flowers. Each fruit has a tuft of white hairs attached.

Red Baron Japanese Blood Grass foliage

Red Baron Japanese Blood Grass foliage

(Photo courtesy of NetPS Plant Finder)

Red Baron Japanese Blood Grass foliage

Red Baron Japanese Blood Grass foliage

(Photo courtesy of NetPS Plant Finder)

Red Baron Japanese Blood Grass

Red Baron Japanese Blood Grass

(Photo courtesy of NetPS Plant Finder)

Height: 18 inches

Spread: 12 inches

Sunlight:

Hardiness Zone: 4b

Other Names: Cogon Grass, Japanese Imperial Grass

Ornamental Features

Red Baron Japanese Blood Grass’ attractive grassy leaves are white in color. As an added bonus, the foliage turns a gorgeous dark red in the fall. Neither the flowers nor the fruit are ornamentally significant. The dark red stems are very colorful and add to the overall interest of the plant.

Landscape Attributes

Red Baron Japanese Blood Grass is an herbaceous perennial grass with an upright spreading habit of growth. Its relatively fine texture sets it apart from other garden plants with less refined foliage.

This is a relatively low maintenance plant, and is best cleaned up in early spring before it resumes active growth for the season. It has no significant negative characteristics.

Red Baron Japanese Blood Grass is recommended for the following landscape applications;

  • Mass Planting
  • General Garden Use
  • Container Planting

Planting & Growing

Red Baron Japanese Blood Grass will grow to be about 18 inches tall at maturity, with a spread of 12 inches. It grows at a slow rate, and under ideal conditions can be expected to live for approximately 20 years.

This plant does best in full sun to partial shade. It does best in average to evenly moist conditions, but will not tolerate standing water. It is not particular as to soil pH, but grows best in rich soils. It is quite intolerant of urban pollution, therefore inner city or urban streetside plantings are best avoided, and will benefit from being planted in a relatively sheltered location. This is a selected variety of a species not originally from North America. It can be propagated by division; however, as a cultivated variety, be aware that it may be subject to certain restrictions or prohibitions on propagation.

Red Baron Japanese Blood Grass is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. It is often used as a ‘filler’ in the ‘spiller-thriller-filler’ container combination, providing a canvas of foliage against which the larger thriller plants stand out. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.

Imperata cylindrica is a noxious weed in many areas, but certain cultivars are grown as ornamental grasses in gardens.

Imperata cylindrica is rhizomatous perennial grass native to east and southeast Asia, China and Japan. The species is an aggressive, green leaved plant also called cogon grass or kunai grass. It invades disturbed areas, such as roadsides, pastureland, and forest edges, to form dense monocultures, and has been used for soil stabilization in some areas. In its native areas it has been used for thatching roofs of traditional buildings, weaving mats and bags, and making paper, as well as in traditional Chinese medicine. It has become naturalized in many tropical and subtropical regions areas outside its native range, including the southeastern US as far north as Virginia, and is considered an invasive weed in many places. It was both accidentally and intentionally introduced to the US in the early part of the last century, and despite prohibition on further planting, has continued to spread inadvertently on road construction or agricultural equipment or by other means. Because I. cylindrica is a listed Federal Noxious Weed, a federal permit is required to move it interstate.

Red-leaved Japanese bloodgrass.

A number of cultivars such as ‘Red Baron’ and ‘Rubra’ used as garden ornamentals are typically referred to as Japanese bloodgrass for the red color of the leaves. These are classified as Imperata cylindrica var. rubra or var. koenigii, and are short, cold-tolerant forms (normally listed to zone 5, but known to survive in zone 4b) with smaller rhizomes than the species. ‘Rubra’ has foliage tinged a burgundy color, while ‘Red Baron’ has brighter, cranberry-red coloration. The leaves are a bright green when they emerge in spring, then the red color develops on the tips and progresses down the leaf blade, becoming more intensely colored later in the season.

Imperata cylindrica var. rubra develops red color that intensifies through the growing season.

This red color may actually be a response to colder temperatures, as plants can revert to green when grown in a hot location. Reversions have substantially larger rhizomes than the red cultivars, so rubra varieties have the potential to become invasive. The red cultivated varieties were also thought to be sterile, but may not be. Even ornamental types are prohibited in most southern states, but Japanese bloodgrass can still be grown legally in colder climates where the plants do not spread as rapidly and rarely flower. Imperata cylindrica is not listed as an invasive species in Wisconsin, but even in northern areas it should only be planted in containers or in places where it cannot escape into natural areas.

Ornamental cultivars have red tips on the leaves.

The species is quite variable, growing 2-10 feet tall, although ornamental cultivars are only 12-18″ high. The narrow and sharply pointed vertical leaves have very finely serrated edges embedded with sharp silica crystals that can easily slice through unprotected skin; this feature makes this grass undesirable as a forage plant. The mid-vein of each leaf is lighter in color than the blade and is off center. The upper leaf surface is slightly hairy near the base of the plant, but the rest is smooth. The leaves are light green when young, but the color changes to brown or orange as they age. The ornamental cultivars have red tips on the leaves; the color becomes more vivid later in the season. Flowering is highly variable, and some clones never or only infrequently bloom. Panicles are filled with small seeds, each with a long, fluffy white plume that allows the seeds to disperse easily in the wind.

Backlit leaves glow with color.

The leaves of Japanese bloodgrass are somewhat translucent, and create a spectacular appearance when backlit, so it is most effective in the landscape where it can be viewed with the early morning or late afternoon sun lighting up the leaves from behind, creating a red and green stained-glass effect. It fits well into rock gardens and borders, can be used as an edging plant, or massed as a ground cover. Combine it with fall-bloomers such as ‘Autumn Joy’ sedum or asters to focus attention on the grass when it is at its most intense color. It is also good in containers as long as they get plenty of water.

This is a warm season grass, and the leaves are killed by freezing temperatures. Winter mulching is recommended in zones 5 and 6 until well established. The plants remain dormant through the winter and are slow to emerge in spring.

This species tolerates a wide variety of soils – from wet to dry and from sand to clay – and prefers full sun but will grow in partial shade. The species can be propagated by both seed and rhizomes, but the ornamental types are only propagated by division.

– Susan Mahr, University of Wisconsin – Madison


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Resistance is Futile-Plants that take over your landscape.

This blog is about attractive plants that take over your landscape. They are tempting and for sale at most garden centers.

Star Trek The Next Generation came out 20+ years ago but I was busy building my landscape design practice and raising a stepdaughter so I missed the whole thing.

Maybe I’m just going to seed as I recently watched all seven seasons in short order. I encountered the Borg and was impressed with their ability to take over a universe. The Borg remind me of certain plants that will happily assimilate your entire garden and need to be avoided.

Here’s a list of plants that are as devastating as the Borg and good at propagating their own kind without any assistance. They have an aggressive spreading growth habit and yet they are still sold at most nurseries and garden centers in spite of their thuggish nature. Be warned.

Houttuynia cordata ‘Chameleon’ Photo Source

Here is a beauty of a beast: Houttuynia

Houttuynia cordata ‘Chameleon’ – I’ve never known anyone who (once it was planted ever managed to get rid of it. It is famous for aggressive roots that will grow through other plants and overpower them. It can seed although it hasn’t in any of my clients gardens because I never use it. Look at how cute the variegated leaf is!

Japanese Bloodgrass, Imperata cylindrica ‘Red Baron’, can spread indefinitely

Japanese Bloodgrass Spreads

Imperata cylindrica ‘Red Baron’ or ‘Rubra’- Japanese blood grass is a spreader but it can be dug out and eventually (as in years of work later) be banished but don’t sacrifice your time to this plant…you will be sorry!!

Ribbon Grass, Phalaris arundinacea

Ribbon Grass is on the Fence

Ribbon Grass, Phalaris arundinacea, is a plant that can be very difficult to eradicate but if a designer suggests it for a contained area that doesn’t mean they are a newbie. It is planted in a parking lot that I frequent. It’s been trapped there over 9 years and has not escaped. I myself have never used it in a design but it is very very low maintenance. Here is an article regarding success in killing the ribbon grass.

This stand of Aspens (Populus tremuloides) started out as one trunk!

Aspen Trees

Aspen trees, Populus tremuloides, are beautiful in a forest but not good for tiny city plots. One tree will become many and fill your soil space with invasive roots that lift walkways, invade foundations and water lines and leave companion plants with no water or nutrition. See this great article from designer pal Beth Goodnight regarding the evils of aspen and some alternative suggestions.

Keep Mint in a Pot

If mint gets away from you – you will never get rid of it. Some people plant it in a pot and keep it on a concrete patio. The roots can escape from the pot and once it spreads in your soil you will have it forever so I never set my pot of mint into a planting bed. I like having mint for soups but it is strictly a container plant.

Japanese Anemone is beautiful but travels fast

Japanese Anemone and Bishops Weed in the Right Spot Only

Japanese anemone, Anemone sp., should only be used by experts. This one is very very seductive and over the top beautiful. It travels by root which is the problem. I like to use it in very low maintenance planting plans/landscape designs and in parking strips where it is easily contained. It doesn’t seem to invade the lawn so I’ve used it in plant borders too.

Bishops weed, Aegopodium podagraria, should be planted by people who know exactly what they are in for. It can be contained in the parking strip or a low maintenance planting where you have nothing but shrubs. Large shrubs with bishops weed as a ground cover can be a functional landscape choice. If I use it I have a rule: You are not allowed to ever give a start of it to a friend.

There are, of course, many plants besides my short list that should be avoided or used with caution. These plants are the stars of this blog because they are so attractive, tempting and readily available at your local garden center.

Above: Photograph by Tom Murphy VII via Wikimedia.

Japanese bloodgrass is a cool-season, low-maintenance grass with few pests or problems. The biggest issue is when the plant is sited incorrectly. It prefers cool, moist, and sunny locations and tends to revert to green and exhibit invasive tendencies in full shade, which makes it a potential hazard to other plants.

Tip: Watch for green reversions and remove immediately. If you are concerned, you can always plant Japanese bloodgrass in a container and be equally as happy.

Above: See Desert Horizon Nursery for Japanese Bloodgrass information and prices.

Cheat Sheet

  • Whether used as a border, ground cover or edging plant, Japanese bloodgrass will thrive. Also suitable for containers.
  • Japanese bloodgrass attracts butterflies but thankfully not deer.
  • Repeat clumps of grasses to draw your eye forward through a bed and provide a sense of rhythm and continuity. Or plant in groups to produce a sweeping effect.
  • Near translucent red foliage, Japanese bloodgrass can be especially attractive in the landscape (especially when backlit by early morning or late afternoon sun).
  • I. cylindrica is a good companion plant for other upright perennials such as black-eyed Susan or orange Echinacea.

Above: To replicate this planting scheme, a Smokey Ready-Made Border (25 plants, including Imperata cylindrica ‘Rubra’, yarrow Achillea ‘Moonshine’, Kniphofia ‘Tawny King’, switchgrass Panicum virgatum ‘Shenandoah’, coneflower Echinacea ‘Hot Papaya’, Crocosmia ‘Lucifer’ bulbs, and pheasant’s tail grass Anemanthele lessoniana) is £173.75 from Crocus.

Keep It Alive

  • Plant Japanese bloodgrass in full sun for the most vibrant color.
  • Moist but well-draining soil is needed to avoid root rot.
  • Established plants can tolerate less water, but for the best appearance water weekly. Tip: Reduce water during its dormant winter period.
  • Avoid cutting back Japanese bloodgrass until early spring (before new growth begins). At that time, cut back bloodgrass to the ground or simply give it a haircut to remove winter damage.

See more growing tips in Japanese Bloodgrass: A Field Guide to Planting, Care & Design in our curated Garden Design 101 guides to Grasses 101. For more ways to use ornamental grasses in a landscape, see:

  • Leaves of Grass: 9 Ways to Create Curb Appeal with Perennial Grasses
  • Expert Advice: 8 Tips for a Meadow Garden from Grass Guru John Greenlee
  • The Bostonians: A Modern Agrarian Landscape in New England

What is it? Grasses are all the rage but I can’t help but take against the ones that look dead even in the height of summer. Blood grass (Imperata cylindrica ‘Rubra’) looks very much alive, with 40cm tall strappy leaves that flush a dramatic shade of red in summer.

Plant it with? Nurseryman Adrian Bloom likes to see this grass en masse planted as a flowing “river”: it looks fine set against grasses with contrasting leaves, such as the silver-grey foliage of blue wheat grass (Elymus magellanicus) or blue fescue (Festuca glauca).

And where? This grass likes its roots in moist soil, so avoid places where it will dry out. The tricky bit is you need to give it sun for the best leaf colour (although a bit of shade won’t harm), so make sure the soil is loaded with humus.

Any drawbacks? In warmer climes it can revert to the species and become invasive, although this shouldn’t be an issue in the UK. Make sure you apply mulch for winter protection when the plant dies back in autumn.

What else does it do? Blood grass is also peerless in pots: on its own, or I’ve seen a stunning display in a container ringed around with black mondo grass (Ophiopogon planiscapus ‘Nigrescens’). Just keep it well watered.

Buy it Buy one 9cm potted plant for £11.99, or two for £23.98 and get one plant free. All orders include free p&p. Call 0330 333 6856, quoting ref GUA634. Or visit our Reader Offers page. Delivery from April.

Caring for Japanese Blood Grass

Japanese blood grass (Imperata cylindrica ‘Red Baron’) is a unique ornamental grass that spreads quickly and serves well as a border plant, ground cover, and filler. Japanese blood grass is also commonly planted in rock gardens and adds flair to your Japanese garden. It is a cultivar of Imperata cylindrica, a perennial grass native to Asia, Africa, India, Micronesia, and Australia. Imperata cylindrica has been used in traditional Chinese medicine and for making thatched roofs and baskets. Japanese blood grass has been cultivated for ornamental purposes; its burgundy or red tips add a unique aesthetic characteristic.

Japanese blood grass requires a long, hot growing season. It reaches 12 to 18 inches high and clumps spread 12 to 36 inches wide.

After planting Japanese Blood Grass, follow these care tips for healthy growth and maintenance.

1. Watering Japanese Blood Grass

Japanese blood grass prefers moist soil, so a regular watering schedule will help the grass grow more vibrantly. If you allow Japanese blood grass to dry out during times of drought for too long, it will not recover. Allowing it to dry out for a short time will merely result in a loss of leaves.

2. Feeding Japanese Blood Grass

There are several options for fertilization. Choose one of these options for best results.

Use a quick-release water-soluble fertilizer every couple of weeks during the growing season.

Use a slow-release fertilizer once each growing season. Work the slow-release fertilizer into the soil around the plant.

Improve soil by mixing with organic materials such as fish emulsion, bone meal, and/or manure.

Purchase an organic complete fertilizer like Plant-tone on April 1st, May 15th, July 4th, August 15th and October 1st.

If using a granular fertilizer, don’t allow the granules to touch the leaves.

3. Controlling and Propagating Japanese Blood Grass

Imperata cylindrica spreads quickly by the wind spreading small seeds, and by rhizomes. It has become naturalized in many areas of North America, Europe, Northern Asia, and Africa. In some areas it is considered an invasive weed because of its quick growth, which can take over growing areas quickly. Some state government in the southeast U.S. have taken moves to eradicate it, even prohibiting it from being propagated. You can stop the growth of Imperata cylindrica by using herbicides. Burning off is not suggested as the grass burns extremely hot and can damage surrounding plants and/or people.

The cultivar, Japanese Blood Grass, is not nearly as invasive, but its quick growth can still be controlled by removing blades that turn completely green. Also, after the blades flower and then turn tan or brown, cut down to the ground. Japanese blood grass can be propagated by dividing the rhizomes in the spring.

4. Winter Care for Japanese Blood Grass

To help Japanese blood grass survive cold winters, the grass will overwinter better if the soil is well-drained, with no standing water that can rot the roots in winter.

Grow Japanese blood grass for its unique, distinct beauty and low-maintenance requirements!

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