Carex oshimensis [KAR-eks, o-she-MEN-sis] is a member of the Cyperaceae or sedge family and hails from the rocky slopes and dry woods of Japan’s Honshu Island.
This evergreen perennial is commonly referred to as:
- Oshima kan suge
- Carex Evergold
The plant’s genus name is derived from the Latin and means “cutter.” This is a reference to the plants very sharp stems and leaves.
Other Varieties of Carex found in the landscape:
Carex Evergold Care
Size & Growth
Oshima kan suge reaches a maximum height of about 1’ foot with a spread of approximately 1.5′ feet.
This fine-textured ornamental grass grows in low, mounded clumps.
The plant produces most of its growth early in the springtime before temperatures exceed 75° degrees Fahrenheit (24° C).
The plant’s narrow, variegated leaves are about 16″ inches long.
Leaves are dark green with a creamy yellow central stripe.
Flowering & Fragrance
In the springtime, very small, insignificant, pale brown flower spikes appear.
Deadheading is unnecessary.
Light & Temperature
This cool-season ornamental grass can do well in part shade or full sun.
The leaf colors are richer and more attractive in partial shade.
The plant cannot tolerate full shade.
Carex Evergold is winter hardy in USDA hardiness zones 5 through 9.
It does best in a warm, dry climate and does not do well in a hot and humid climate.
Watering & Feeding
Carex is easy to grow in a wet to a medium setting and requires little or no fertilizing.
Soil & Transplanting
This sedge can do well in any average garden soil, but it prefers moist, slightly acidic soil.
This type of grass may be transplanted either in the autumn or in the springtime.
In very cold settings, it is best to transplant in spring because winter freezing may cause freshly planted rhizomes to heave out of the ground.
Grooming And Maintenance
In areas with mild winters, Carex oshimensis is evergreen.
In this setting, leave the foliage in place until springtime and then shear or mow to stimulate fresh growth.
In areas where it may freeze, it’s best to cut back the foliage before winter so it can grow back fresh in the spring.
Alternately, you may wish to simply comb through the foliage in the winter months to remove dead leaves.
If you have left the plant standing through winter, early in the springtime, cut the plant back by about a third or shear or mow closely.
How To Propagate Japanese Sedge
Plants spread naturally and slowly via rhizomes.
Propagate by rhizome division, which is best done during the springtime.
Japanese Sedge Main Pest or Disease Problems
Well cared for Oshima kan suge is virtually pest and disease-free.
Is This Carex Toxic or Poisonous?
This sedge grass is non-toxic to livestock, horses, dogs, cats, birds, and people.
Is Evergold Invasive?
Carex Evergold spreads very slowly and can simply be mowed down in areas where it is not wanted.
Suggested Carex Evergold Uses
This deer-resistant plant is an excellent choice in mass plantings or used as a groundcover in partially shaded areas, such as woodland gardens.
In a smaller garden, it makes a nice accent plant or use it as an edging along pathways.
Because it does well with moist soil, it makes a good filler for low spots and is very attractive along stream banks or around a pond.
It also makes a nice rain garden addition.
Individual plants can do fairly well in containers.