Carex tumulicola (KAR-eks too-mew-li-KO-la) is a grass-like herb native to the west coast of the United States and parts of Canada.
This ornamental grass is found on Channel Island and coastal regions ranging from San Luis Obispo County to Humboldt County in California.
It is also found in the coastal regions of Oregon and Washington state.
The plant grows well in a wide variety of settings ranging from woodlands to meadows to prairies.
Unlike many of its cousins in the Cyperaceae family, it does not do well in a wetland setting.
This member of the sedge (rush) family is a perennial plant which may reseed itself but spreads primarily through rhizomes.
The plant’s genus name, Carex, is Latin for “cutter” and refers to the sharp leaves and stems of this ornamental grass.
The specific epithet, tumulicola, refers to the plants’ low, mounded growth habit.
The term seems to have been derived from several Latin terms.
Tumulus is the Latin for “mound.” Tumere is the Latin for “swell.”
Cola/incola means “inhabitant or dweller.”
Common names include:
- Split-awn Sedge
- Splitawn Sedge
- Berkeley Sedge
- Slender Sedge
- Foothill Sedge
There are more than 1500 different species of Carex worldwide, and it is hard to tell them apart.
For example, for some time, Carex divulsa, which is a European native, was mistakenly sold as Carex tumulicola in California.
This was quite unfortunate because divulsa spreads aggressively and can withstand colder temperatures than tumulicola.
Carex Tumulicola Care
Size & Growth
Split-awn Sedge grows and spreads slowly.
Individual plants can attain a height of 1′ or 2′ feet and a spread of 2′ or 3′ feet.
Slender Sedge’s evergreen, grass-like leaves are about an eighth of an inch wide and about eighteen inches long.
They are a medium shade of green.
Flowering & Fragrance
The flowers of Splitawn Sedge are so small as to be unnoticeable.
They appear in the springtime (April-May) at the top of two-foot-high stems.
Flowers are very small, insignificant, and scentless.
They may be green, brown, or cream-colored.
Birds greet them with great enthusiasm.
Light & Temperature
Berkeley Sedge can grow in light ranging from partial shade to full sun in its native west coast setting.
It is winter hardy in USDA hardiness zones 8-10 and can grow as a perennial in these zones.
In lower hardiness zones, it is possible to grow it as an annual.
Watering & Feeding
Foothill Sedge likes fairly consistent medium moisture, but it can tolerate occasional short periods of drought.
In the summertime, water deeply once a week.
Early in the summer, provide a light meal of nitrogen-rich plant food.
Soil & Transplanting
Split-awn Sedge can do well in all sorts of soil as long as the drainage is good.
For the best performance, provide a light, airy soil, well amended with organic matter to help retain moisture.
For successful transplanting, follow these steps:
- Clear the intended planting area of all grass and weeds.
- Spread a good layer of organic compost several inches deep.
- Plant your young plants or plugs 6” apart for quick coverage or a foot apart for slower results.
Grooming & Maintenance
Splitawn Sedge is a low-maintenance ornamental grass which can tolerate light foot traffic and be mowed at the end of the season.
Once plants become established, their rhizomes spread, and the blades of the plants smother out any emerging weeds.
If you wish to limit reseeding, cut back or mow the flower spikes before they turn brown and drop seeds.
The ideal height to stimulate bushier growth is about 4″ inches.
How To Propagate Foothill Sedge
Berkeley Sedge is very easy to propagate as it spreads on its own through self-seeding and rhizome spread.
Speed up spread by dividing larger plants early in the springtime and relocating them.
Although it is possible to create an entire lawn from one plant with a little patience, you needn’t worry about Slender Sedge taking over.
It spreads steadily, but won’t get away from you.
Foothill Sedge Main Pest or Disease Problems
This carefree ornamental grass does not have any problem with pests.
If overwatered, it may develop rust, smut, or leaf spot.
Is The Plant Toxic Or Poisonous?
Unlike some types of sedge, Foothill Sedge is non-toxic.
Is The Plant Invasive?
Carex tumulicola is not invasive, but its cousin, Carex divulsa, is.
The two are often mistaken for one another and often share common names.
Be careful to get the right plant from the start.
Be sure to verify the plant you are purchasing is tumulicola, not divulsa.
Suggested Carex Tumulicola Uses
In USDA hardiness zones 8-10, Split-awn Sedge makes a nice ground cover or lawn substitute.
It is an especially good choice in areas having trouble with erosion.
Although the flowers are insignificant, Berkeley Sedge is a nice addition to your bird garden because birds greatly appreciate the seeds.
In smaller gardens, Splitawn Sedge makes an attractive border or even an accent plant.
It is pretty when planted alongside garden ornaments and features and looks nice on the verge of a pond.
Because it is non-invasive, Slender Sedge makes a good filler between trees and established plants.
It will not overwhelm them or usurp their space.
Foothill Sedge is a very versatile, deer tolerant plant adaptable to a wide variety of settings and soil conditions.