Japanese sedge
Carex kobomugi · Cyperaceae
Japanese sedge (Carex kobomugi) is a perennial grass or grass-like plant in the Cyperaceae family. It is introduced to North America rather than native. USDA records it as hardy in zone 5 and warmer, down to about -18°F.
⚠ Invasive or noxious status. USDA lists this plant with an invasive or noxious weed status somewhere in its range. Check your state's noxious weed list before planting it — in some states it is illegal to sell or plant.
Both flags are quoted from USDA PLANTS, not inferred.
At a glance
| Type | graminoid USDA |
|---|---|
| Lifecycle | perennial USDA |
| Native status | introduced USDA |
| Mature height | 1 ft USDA |
| Light | full-sun USDA |
| Water need | low USDA |
| Growth rate | slow USDA |
| Soil pH | 5.7–7 USDA |
| Bloom | June USDA |
| Flower color | Brown USDA |
| Hardiness zones | 5 and warmer USDA |
| Guild layer | ground-cover Derived |
| Nursery availability | Routinely Available USDA |
USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.
Growing conditions
It needs full sun. USDA rates it as having low water needs once established. Its drought tolerance is rated high. It is recorded on soils from pH 5.7 to 7 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 5.
Size and growth
At maturity it reaches about 1 ft, making it a low, mat-forming plant. It grows slowly.
Bloom period
USDA records a bloom period of June. Flowers are brown.
A flowering date, not a pollinator rating.
Foliage, flower and season
Summer foliage is green, coarse in texture. Its flowers are not conspicuous — a plant for form and foliage. Its active growth period is spring and summer. USDA rates its lifespan as moderate.
What the site needs to provide
USDA records it across sites receiving 36 to 55 inches of annual precipitation. It needs at least 155 frost-free days to finish its season. It roots to at least 16 inches. Fertility requirement: low — no feeding needed on ordinary garden soil.
Propagating it
Propagate it from container stock and sprigs. It spreads vegetatively at a slow rate.
Resilience and wildlife
Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated high. Its growth form is recorded as rhizomatous.
Role in a guild
Ground cover. In a layered planting this is the lowest layer — it shades soil, holds moisture, and suppresses weeds. The layer is derived by a fixed rule from growth habit and mature height.
Tags
Related plants
Others in Carex
- thicket sedge Carex abscondita
- greenwhite sedge Carex albolutescens
- eastern narrowleaf sedge Carex amphibola
- Columbian sedge Carex aperta
Similar role and hardiness
- Jack in the pulpit Arisaema triphyllum
- Mexican rush Juncus mexicanus
- turkey tangle fogfruit Phyla nodiflora
- meadow bistort Polygonum bistorta
Where this data comes from
Every value on this page comes from the USDA PLANTS database record for symbol CAKO2, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.
- Quoted from USDA PLANTS: active growth period, Bloom, Bloom end, browse palatability, cold stratification, Drought tolerance, fall conspicuous, fertility requirement, fire tolerance, Flower color, flower conspicuous, foliage color, foliage porosity winter, foliage texture, frost free days min, fruit conspicuous, growth form, Growth rate, Hardiness zones, Invasive status, Lifecycle, lifespan, Light, Mature height, Minimum temperature, Native status, Nitrogen fixation, Nursery availability, precipitation max in, precipitation min in, propagation, resprout ability, root depth in, seed spread rate, Soil pH, Soil pH (upper), Tolerance of wet soil, Toxicity, Type, vegetative spread rate, Water need.
- Derived by a fixed rule from those columns: Guild layer.
Read our full data sources and methodology.
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