HIGH EVERGREEN GRASSES
Most evergreen grasses are between 5-50 cm high. If you are looking for man-sized evergreen ornamental grasses, then the choice is very limited, the group clumping (non-invasive) bamboos in the genus Fargesia are a better choice for most situations from shade to sun (see the bamboos tab).
The highest evergreen ornamental grass is Cortaderia (Pampas Grass). There are different species and cultivars of this South American native. Joint characteristics are the long, blue-green to gray-green foliage with sharp edges, which forms a dense clump, and the creamy-white, gray to silvery-white large, dense plumes which rise above the plant. Keep in mind that after severe winters Cortaderia needs to be pruned because the evergreen foliage cannot withstand prolonged severe frost. We only grow the hardiest and more compact form Cortaderia 'Pumila', about 2 m high.
Miscanthus flavidus sp. Taiwan is a new ornamental grass which stays green in most winters This ornamental grass forms a nice clump of about 1 meter high. The leaves turn to bronze-green in spring and autumn. The copper-colored plumes appear often already in mid summer. Sp .’Taiwan' attracts the attention of many visitors after winter. Limited availability.
LOW EVERGREEN GRASSES
In the group lower evergreen grasses from 5 to 50 cm is lots of choice, especially in the groups of species Carex, Luzula, Liriope and Ophiopogon. I have highlighted the species that we know the properties of the nursery and for use in garden design. Disease Sensitive and short-lived species such as Festuca many programs, Sesleria and some Carex, Stipa and Deschampsia are taken out of our collection for that reason.
Acorus gramineus 'Hakiro Nisiki' (Japanese dwarf sweet flag, member of the Aroid-family) is the smallest member of the family sweet flag (5-10 cm). This Japanese selection has a dense, grassy leaf waves on short creeping rhizomes. ‘Hakiro Nisiki‘ has striking lime green to yellow-green evergreen foliage and is very useful to form a low, ground covering sod along border edges, planting in containers or between stones and boulders. The Japanese Dwergkalmoes requires a humus-rich, moist soil in partial shade.
Acorus gramineus 'Ogon' Japanese Sweet Flag (Japan) Winter Green. This species from Japan has a striking lime green banding over its leaves and is 20-40 cm high.
An exiting new species in the size of ‘Ogon’ with complete lime colored leaves is Acorus gramineus ‘Oborozuki’ (‘Golden Delight’).
Carex foliosissima 'Irish Green' Japanese sedge (Japan) evergreen. Rarely seen such a beautiful green color with an ornamental grass. This is a rare evergreen Carex from Honsu, Japan, can be situated in sun and in the shade are a gorgeous deep green compact carpet. It is a strong plant that makes new shoots by short spurs. As a result, this strain is suitable to stabilize a slope or to fill a planting container. Also suitable as an accent in a border and in beds with other grasses and perennials. Shade and drought is surprisingly well tolerated, though the plant grows better in humus-rich, moist soil in partial shade to sun. Does well as a groundcover in difficult places. Plant height 25 to 35 cm. Also useful in planting containers on terraces and roof gardens.
The group of Carex morrowii consists of clumping and spreading types; typically is the stiff, upright leaves. Carex morrowii 'Gilt Edge' has a wide creamy-white margin. The vertical, linear accent of this plant is well used alongside foliage plants and ferns. Shade and drought is surprisingly well tolerated, though the plant grows better in humus-rich, moist soil in partial shade to sun.
Carex morrowii 'Ice Dance' is a variegated Japanese spreading form. The leaves are strongly cream banded at the edges. This remarkable selection has been introduced by Barry Yinger from Japan and is 25-40 cm high, depending on the location. ‘Ice Dance’ is undemanding, can be in relative shade if planted in sunny places.
The selection Carex morrowii 'Gold Band' is the strongest golden signed cultivar and is moderately spreading. A beautiful species to light up dark corners.
Carex morrowii 'Variegata' is a clumping, reliable, evergreen sedge with narrow creamy-white margin from Japan. It is one of the best evergreen species in the shade and partial shade and grows up to 30 cm high. Blooms in spring with clusters of yellow on brown steal. The botanical clumping green form Carex morrowii and the smaller selection Carex morrowii 'Mosten' I use regularly in my garden designs.
Carex oshimensis (syn. haijoensis) is another important group of Japanese sedges. This type is always a round compact clump with gracefully arching, narrow tipped leaves.
Carex oshimensis 'Evergreen' is the botanical form and is 30 to 40 cm high and 40 to 50 cm wide eventually; clearly larger than the colored cultivars of this species. The excellent evergreen foliage forms a dense tussock from the center. Carex oshimensis is very suitable for smaller and larger plant areas where deep green and evergreen is required. Other green shapes like ‘J.S. Greenwell’ would remain more compact. At the nursery various colored selections are available like Carex oshidensis 'Evergold' with yellow edges leaves and compact growth. Also variegated white and lime green to yellowish green cultivars are very interesting to apply.
Carex pendula or Giant Sedge forms large evergreen clumps up to 60 cm high and is in the summer, adorned with long, drooping inflorescences up to 1,70m. Far after flowering one can enjoy the decorative appearance of this plant. C. pendula is one of the few grass species that does well in dry shade, although a moderately humid place is preferred.
Carex sp. Nanking is a new low broadleaf evergreen species from Japan with a nice layered leaf structure. ‘Nanking’ grows upto 30-40 cm high and spreads slowly. Limited available
Carex scaposa is another oddity from Yunnan, China with soft green broad leaves and later on in the season unique pink flower spikes which are visited by insects. Carex scaposa grows best in partial shade in a moist, humus-rich soil. In severe winters some protection is recommended. Limited availibility.
Carex (dolichostachya) divulsa 'Kaga Nishiki' is an elegant variety with a dense canopy and narrow variegated leaves. 'Kaga Nishiki grows up to 20 to 30 cm. Shade and drought is surprisingly well tolerated, though the plant grows better in humus-rich, moist soil with more sun. 'Kaga Nishiki' grows in dense clumps with short side shoots which slowly creates a dense carpet. Recommended.
Although not formally a grass Japanese horsetail is presented here. Equisetum ramosissimum 'Japonicum' has green bamboo-like stems which are composed of individual segments. Each segment has a black edge. As a garden plant, used it with root barrier, it grows to a height of about 100-130 cm and well used in combination with foliage plants because of strong vertical lines. Even as a container plant. Equisetum heymale 'Robustum' is a large species that grows under favorable conditions to a respectable 150-200 cm. Both species can be pruned. Equisetum is evergreen, but if stalks snap by heavy snowfall they can be cut back.
Liriope are evergreen herbaceous clumping lilies from Asia. At our nursery there are always several kinds in stock. Liriope is 15-30 cm tall and comes in the autumn flowering. This evergreen plant is useful in larger groups in the foreground, as an edge plant and in large planters. Prefers a humus-rich, moist soil.
Liriope muscari 'Royal Purple' owes its name to the larger, fuller and blue-purple inflorescences. Another pair of blue shapes 'Moneymaker' 'Ingwersen' and 'Big Blue'. Liriope muscari 'Gold Banded' is a variegated selection of Liriope has somewhat coarser, broader leaves compared to the botanical form. The yellow bands in the longitudinal direction of sheet have been especially during the new sheet forming the most intensive. Later in the year the greens dominate in the leaves. Makes thick, purple flower clusters in late summer. This variety has proved surprisingly strong after the last cold winters. Liriope muscari 'Monroe White' has creamy white flower plumes in late summer. Liriope spicata is an excellent spreading groundcover with lavender flower spikes. At the nursery more species and cultivars can be found.
Reineckia carnea syn. Liriope hyacinthiflora is a narrow leaved relative of Liriope and Ophiopogon and is an evergreen ground cover with bright green leaves, into the deep shadow. Typically are the flesh-colored flowers in autumn are orchid-like followed by red berries. It grows about 20 cm tall and prefers a humus-rich top layer to retain moisture. Then it's an easy-growing species. Beautiful in the undergrowth or border plant.
Ophiopogon is related to Liriope with the difference that this Asian lily type has a different inflorescence and is usually spreading moderately. Ophiopogon is an important, very useful group for undergrowth and ground cover. Ophiopogon japonicus is a narrow-leaved ground cover up to about 25 cm high. Sometimes special cultivars are also available as Ophiopogon japonicus ‘Kijimafukidama’. A similar species with small leaves but clumping is Ophiopogon chingii.
Ophiopogon japonicus 'Kyoto Dwarf', Temple Grass is the much sought low and very compact Ophiopogon, originally used in Japanese gardens and temples. This Japanese mini snake beard with dark green leaves, grows in dense evergreen clusters into a dense groundcover of 5-10 cm high. It flowers with small white bells followed by striking steel blue berries. Beautiful in combination with ornamental grasses, foliage plants and between being pruned bamboo. Also suitable for large scale planting. Humus-rich, moist soil in partial shade to sun.
Ophiopogon planiscapis ‘Nigrescens’ (Black Snake Beard) is a striking plant with truly black, ribbon-like leaves. The creamy white flower clusters have a purple tinge and are followed by black berries. This low ground cover (15-25cm) takes some time, but after a few years he forms a perfect dense ground cover math. Black Snake Beard is evergreen or should we say winter black? Nice to use as undergrowth of a well pruned black bamboo and in combination with eg Japanese Blood Grass! Also useful in containers. Requires a moist, humus-rich soil. Preferably in sun to partial shade. Grows also in full shade but is less black. The selection Ophiopogon 'Black Smaragd' is black and green. A black narrow-leaved cultivar is Ophiopogon 'Black Needle'.
Ophiopogon planiscapis 'Smaragd', the Green Snake Beard has deep green leaves and creamy white flowers with a dark stem. The berries are dark blue. Shade and drought is surprisingly well tolerated, though the plant grows better in humus-rich, moist soil. Does well as a ground cover in combination with ornamental grasses, Acer and bamboo. Is also used as roof gardens and facade planting.
The new hardy species Ophiopogon jaburan resembles planiscapis 'Smaragd' but slightly wider lighter green leaves and bright white bells on a green stalk. Grows more slowly. Jaburan is limited available.
Ophiopogon wallichianus 'Intermedius' is an interesting new very hardy species with very narrow, grassy evergreen foliage. The open cluster shaped flowers are purple and hang on curved stalks. The berries are dark in color. Recommended!
Sometimes other rare varieties are available, like the white variegated leaved Ophiopogon japonicus 'Kigimafukidama', variegated version of Kyoto Dwarf; Ophiopogon japoncus 'Snow Globe', Ophiopogon japonicus 'Shiroshima Ryu' and the super small variety: Ophiopogon japonicus 'Gyoko Ryu'(='Super Dwarf' USA)
Phaenosperma globosa is a newcomer from China and Japan, making a full tuft of leaves 50-60 cm wide, palm-like long, slender spikes of up to 150 cm which are topped with symmetrical gems. This grass can be seen as a hardy alternative to exotic palm grass (Setaria palmifolia) which in summer is planted by enthusiasts in gardens. Spectacular grass which needs certain space to be appreciated.
Stipa (Nassella) tenuissima 'Pony Tails', Mexican feather grass is one of the most fine-leaved grasses. The straw yellow flowering panicles swaying gently in the breeze. This species blooms from June to September and requires a very well drained soil in full sun. Also suitable to use in gravel ridges, between stepping stones and in containers. Although it is a short-living species, they can spread slowly and remain in position in the garden. Height about 30 cm. A similar species is Stipa pulcherrima also with a very fine texture and slender plumes. Stipa barbata is slightly larger but is more sensitive to wet winters. After the winter comb the plants. After the winter the old foliage short to ground cutting stimulates new growth quickly. Very nice combined with Yucca and palm trees. Usually available later in Spring.