Focus on: Grasses
Movement, structure and seasonal interest from a versatile group of perennials
Ornamental grasses have become a defining feature of contemporary planting. Once treated as edge-of-border curiosities, they are now a popular choice in planting schemes, used for the rhythm and texture they bring across the seasons. This reflects the wider trend toward naturalistic and ecological planting, and they suit the kind of low-input, long-performance schemes commonly specified today.
Grasses move in the wind, catch low light, and hold their form well into winter, giving a planting scheme a sense of life when surrounding perennials have died back. They mix readily with perennials, shrubs and trees, and they read at a distance as well as up close.
Heights range from ankle-high mounds of Festuca glauca to two-metre plumes of Miscanthus sinensis, and habits run from tight clumps to airy veils. Some grasses bring early-season presence; others peak through late summer and autumn. That variety is part of what makes them so useful in planting design.
Grass seed feeds finches and other small birds through autumn and winter. The standing stems provide overwintering shelter for invertebrates including ladybirds and lacewings, and several native grass species are larval food plants for skipper butterflies and a number of moths. Used well, ornamental grasses extend the season of habitat as much as the season of interest.
Most ornamental grasses thrive on poor to moderate soils, need little irrigation once established, and need only a single annual cutback to perform year on year. Among contemporary planting groups, few match grasses for value over the long term.
Key Characteristics of Climbing Plants:
✓ Deciduous shrub or small tree
✓ Noted for colourful winter stems
✓ Spring flowers and autumn foliage colour
✓ Tolerates wet soils and exposed locations
✓ Low maintenance and reliable structure
✓ Valuable for wildlife
✓ Effective in mass planting and mixed borders
Did You Know?
The grass family, Poaceae, is one of the largest plant families in the world, comprising more than 10,000 species worldwide. Alongside ornamental grasses, the family includes cereals, bamboos and many of the turf grasses used in parks and gardens.
Cool-season and warm-season grasses
Most ornamental grasses fall into one of two groups, cool-season or warm-season, and the difference affects when they grow and how they should be cut back.
Cool-season grasses are active when temperatures are moderate. They start into growth early in spring, flower from late spring through midsummer, and often slow or rest through hot dry weather before reviving again in autumn. Calamagrostis × acutiflora ‘Karl Foerster’, Deschampsia cespitosa and Festuca glauca sit in this group, along with the various Stipa species.
Warm-season grasses come into growth later, peak through midsummer and autumn, and cope better with heat and drought. Miscanthus sinensis, Panicum virgatum and Pennisetum alopecuroides belong here.
A scheme that mixes the two groups always has something doing the visual work, regardless of the season. The difference also affects when to cut back: cool-season grasses are typically tidied in late winter before new growth begins, whereas warm-season grasses can be left a little longer.
Ornamental grasses for landscape planting
Calamagrostis × acutiflora ‘Karl Foerster’
Calamagrostis × acutiflora ‘Karl Foerster’
A deciduous, cool-season grass with tight, narrow clumps of fresh green foliage and vertical flowering stems to around 1.5 m by early summer. The feathery panicles tighten to a buff column as the season progresses, and hold their shape through autumn and winter. Works well in mass planting, mixed borders and along long avenues or driveway approaches, often without staking even on exposed sites. Calamagrostis provides structural punctuation and rhythm against softer mounding partners. Performs in full sun and tolerates a wide range of soils, including damp ground.
Stipa gigantea
Commonly known as golden oat grass, Stipa gigantea forms a low evergreen tussock of fine, arching foliage. Oat-like flower spikes rise to 2 m or more in early summer, catching low light beautifully and remaining attractive into autumn. Effective as an architectural focal point in larger schemes, gravel gardens and open borders, where it has space to be seen. Performs in full sun on well-drained soil; prefers an exposed position and dislikes crowding.
Miscanthus sinensis
A large, clump-forming warm-season grass with arching ribbon leaves and silken plumes from late summer into autumn that fade to soft buff and silver tones through winter. Useful as backdrop planting, informal screening, or as a singular focal point in mixed borders. Cultivars range from compact 1.2 m forms such as ‘Kleine Silberspinne’ to taller, more architectural selections including ‘Malepartus’ and ‘Morning Light’. Tolerant of most soils, though best growth comes on moisture-retentive ground in full sun.
Stipa gigantea
Miscanthus sinensis ‘Kleine Silberspinne’
Carex buchananii
An evergreen sedge forming upright clumps of fine, copper-brown foliage to around 60–80 cm. Brings warmth, texture and movement to gravel gardens, mixed borders and naturalistic planting, where its airy habit contrasts well with broader-leaved companions. Useful for year-round structure and particularly effective in contemporary schemes. Prefers full sun or light partial shade on well-drained soil and tolerates exposed conditions once established.
Carex testacea
A graceful evergreen sedge with arching green foliage flushed orange and bronze, especially in autumn and winter. Forms soft mounds to around 50–70 cm, adding colour and movement to mixed borders, gravel gardens and informal planting schemes. Combines well with perennials and other grasses, bringing soft texture through the year. Best in full sun or partial shade on free-draining soil.
Carex buchananii
Carex testacea
Anemanthele lessoniana
Deschampsia cespitosa
A native cool-season grass forming dense evergreen tussocks of fine, dark green foliage with airy panicles that hover above the leaves through summer in soft greens, golds and bronzes depending on the cultivar. Valuable for the lower, cooler parts of a scheme and well suited to naturalistic and prairie-style planting. Brings a soft, hazy texture and a gentle vertical lift that reads beautifully when backlit. Thrives in partial shade and tolerates damper soils than most other grasses; strong cultivars include ‘Goldtau’ and ‘Bronzeschleier’.
Anemanthele lessoniana
An evergreen grass forming a graceful, arching mound of fine foliage that flushes orange, copper and bronze through autumn and winter. Reaches around 1 m in flower with airy purple-bronze panicles in late summer. Useful for year-round colour and texture in mixed borders, gravel gardens and informal naturalistic planting, particularly where seasonal shifts in colour are valued. Brings a softer, less formal habit than Calamagrostis or Miscanthus, and self-seeds gently in a way that suits relaxed schemes. Prefers full sun or partial shade on free-draining soil.
Stipa tenuissima
Commonly known as Mexican feather grass, Stipa tenuissima forms fountain-like mounds of hair-thin foliage to about 60 cm. The pale flower heads emerge green in early summer and bleach to soft straw, moving in the slightest breeze. Effective in mass planting, gravel gardens and the front of mixed borders, particularly where its movement can be appreciated against more solid backdrops. Best in full sun on free-draining soil; short-lived and benefits from regular renewal.
Stipa tenuissima
Festuca glauca
An evergreen, dwarf grass with upright, dense tussocks of stiff, blue, needle-like foliage and blue flowerheads in summer that fade to a buff colour. Works well in a container or as part of a gravel garden. The colour and compact habit make it a versatile front-of-scheme grass and a strong textural contrast to greener planting partners. Prefers full sun and well-drained soils, dislikes waterlogged ground in winter, and benefits from being divided every few years to keep clumps fresh.
Pennisetum alopecuroides
A deciduous, clump-forming grass with arching, narrow mid-green leaves and soft, bottlebrush flowerheads in late summer. The flowerheads emerge in shades of cream, soft pink or smoky purple depending on the cultivar, fading to buff and holding well into early winter. Useful in mixed borders, drifts and gravel gardens, where its fine texture and movement contrast with broader-leaved planting partners. Cultivars such as ‘Hameln’ (compact) and ‘Red Head’ (larger, richer-toned) are widely used in landscape schemes. Needs full sun and free-draining soil, and performs best where summers are warm.
Festuca glauca
Pennisetum alopecuroides
Planting and long-term care
Ornamental grasses are among the easiest groups of perennials to establish, but a few practical points improve their long-term performance.
Most ornamental grasses prefer free-draining soil and dislike sitting in waterlogged ground over winter. Where the ground is heavy, the addition of grit or a slightly raised planting position can make the difference between long-term success and steady decline. The exceptions are Deschampsia and Molinia, which both tolerate damper conditions and are useful in those settings.
Spacing should reflect mature habit. Clump-forming grasses such as Miscanthus and Calamagrostis settle into stable, slowly expanding clumps and can be planted as feature points or in rhythmic groupings. Smaller grasses like Stipa tenuissima and Festuca glauca perform best when planted in groups of five or more, where their texture builds into a recognisable element of the scheme.
The annual cutback is the single key maintenance task. Cool-season grasses are best cut down in late winter, before new growth begins, to a few centimetres above the crown. Warm-season grasses can be cut earlier, from late autumn onwards, though leaving the standing stems through winter gives invertebrate shelter and seed for birds, and adds visual interest at a low time of year. Hakonechloa and Festuca glauca need only a light tidy rather than a full cut.
Most clump-forming grasses benefit from being lifted and divided every four to six years, particularly where the centre of the clump begins to thin. Festuca glauca and Stipa tenuissima are short-lived and benefit from more frequent renewal.
Ornamental grasses extend the season of interest into the winter months, provide overwintering shelter for invertebrates and seed for birds at a time of year when most other plants have receded, and reduce the maintenance burden of large planting areas without sacrificing presence. Used in proportion with perennials, shrubs and trees, they give a scheme a sense of weather, time and place that more static planting cannot match.
For schemes that need to perform across years rather than seasons, ornamental grasses are among the most useful and reliable groups in the contemporary planting palette.
For more information about ornamental grasses for landscape planting, speak to the G Team today.