My first foray into ornamental grasses was a disaster: I made the wrong choices, put them in the wrong places, and snipped them back at the wrong time. The result, aside from the splodgy mess, was a confidence knock. But I have since developed a great affection for them, not least in creating my own garden, where slender clumps of Molinia caerulea, and the gentle sprays of Chasmanthium latifolium seed heads, have proved the most enchanting of late-season perennials. Pennisetum ‘Black Beauty’, with its broad abundance of dusky flower spikes, is hands-down the best plant I’ve grown in years.
The popularity and range of ornamental grasses available has never been greater. The stately pampas grass (Cortaderia selloana) used to be one of the very few representatives (and according to urban myth, one in the front garden was a not-so secret symbol that the residents were swingers). But then followed the “new perennial movement” of the 1990s and early 2000s, whose generous tussocky drifts lifted grasses into the mainstream. Now, thanks to the naturalistic aesthetic in gardens, there are grasses for all arenas and in every conceivable form, from low-growers such as fescue and melick to the shimmering fountains of deschampsia, panicum and calamagrostis, whose cultivars seem to double in number each year.
There are many reasons for planting grasses, but there are three main benefits. Firstly, autumn colour – russet, gold and smoke-white eruptions just when you need them. Second, they are the great filler, tying together disparate plants (the flurry of wood melick Melica uniflora underpinning designer Ula Maria’s garden at Chelsea this year no doubt contributed to her winning best in show). And third, movement: a flutter of stems in the lightest breeze draws the eye. Perhaps loveliest of all, though, are their common names, each more bucolic than the last: feathergrass, quaking grass, gossamer grass, wood oats, little bluestem, foxtail barley. They don’t so much roll off the tongue as dangle from the mouth of a straw-hatted yeoman.
So, what went wrong with my first attempt at clumps of stipa and pennisetum in the border? First, shade. There are fantastic grasses for shade, but the aforementioned, like so many, require a south- or west-facing position. The other mistake was to apply a heavy manure mulch in autumn, which ensured that moisture clung to the crowns and rotted their centres. The nail in the coffin was chopping them back too early in dank, dark winter.
Most ornamental grasses prefer well-drained, only moderately rich soils. Beyond this, they require little maintenance or feeding: most can be cut back in one fell swoop in spring – after which fresh shoots will appear – or given a comb through with fingers or fork to remove dead debris.
A watering can of diluted seaweed once or twice in early summer will generally suffice for feeding, and limiting crowding from neighbouring plants will aid fuller growth. And opt for lighter mulches such as straw rather than richer manures. If the plants get too chunky (as is common with, say, pennisetum or miscanthus), you can simply lift them in spring, crudely quarter or halve with a spade, and replant the divisions.
The only question, then, is which to choose from the burgeoning options available.
Grasses for sun
Golden oats (Celtica gigantea)
A stalwart of the sun-baked gravel garden, C. gigantea thrusts sparkling stems over a great mound of airy foliage. Plant individually for best effect.
Buy: knollgardens.co.uk, £12.99
Fountain grass (Pennisetum cv.)Pennisetums are excellent medium-height, late-blooming grasses for sunny sites, smothered in softly bristled plumes. ‘Black Beauty’, or its lighter alternate, P. alopecuroides ‘Hameln’, both act as middle-border statements.
Buy: jacksonsnurseries.co.uk, £9.99
Blue fescue (Festuca glauca)
Another lover of full sun, Festuca glauca has long been favoured for its shimmering blue, “glaucous” mounds, suitable for a container, window box or gravel scheme. The leaves of Festuca ‘Elijah Blue’ verge on silver.
Buy: crocus.co.uk, £4.79
Quaking grass (Briza maxima)
Grown as an annual, quaking grass offers brilliant cut stems, sprinting from tuft to delicate teardrop sprays in just a few months. Grow with for-the-vase flowers like orlaya and cornflower.
Buy: sarahraven.com, seeds £1.80
Reed grass (Calamagrostis × acutiflora)
A natural hybrid named after the German nurseryman who bred it, ‘Karl Foerster’ is still the best-loved calamagrostis: a neat, robust, three-foot perennial with slender straw-coloured flowers. Looks great planted in a “run” or drift.
Buy: macplants.co.uk, £7
Purple moor grass (Molinia caerulea)
Another favourite in my own garden, the UK native Molinia caerulea sends up incomparably delicate stems about 1.5m tall which float beautifully among the late-season perennials such as rudbeckia and aster. Copes with damper conditions.
Buy: celticwildflowers.co.uk, £3.99
Foxtail barley (Hordeum jubatum)
This is another hardy annual grass that can be grown quickly from seed to produce delightful, light-catching heads of barley. I’ve grown it with marigolds this spring and the effect is stunning.
Buy: chilternseeds.co.uk, £2.65
Panicum ‘Heavy Metal’ (Panicum virgatum)
There are umpteen cultivars to choose from for this lofty, upright North American perennial. Panicum virgatum ‘Heavy Metal’ is a vertical eruption of blue-green foliage topped with a purple haze of flowers. Plant in blocks for best effect.
Buy: knollgardens.co.uk
Silvergrass (Miscanthus sinensis ‘Kleine Fontäne’)
Defined by its great height, white-lined leaves and abundant, glinting flowers (not to mention its rock-solid root base), miscanthus is the ultimate all-rounder grass, and the pink-tinged ‘Kleine Fontäne’ its premier cultivar.
Buy: ballyrobertgardens.com, £6.99
Grasses for semi-shade
Tussock grass (Deschampsia cespitosa ‘Schottland’)
I pass a clump of deschampsia on my commute and it has never failed to impress: the popular cultivar ‘Schottland’ flares bronze throughout summer and autumn, tolerating damper soils and partial shade. Plant individually.
Buy: bethchatto.co.uk, £8
Japanese forest grass (Hakonechloa macra)
Hakonechloa remains the garden designer’s default ground cover, and understandably so. As an underplant for trees and shrubs, or drifted through perennial schemes, this low, spring-lush and autumn-blazing grass is as hardworking as it is elegant.
Buy: cowellsgc.co.uk, £12.99
Wood oats (Chasmanthium latifolium)
The quintessential shade grass, this is medium height and airy, and brings gorgeous autumn colour and the most enchanting herringbone seed heads. Best planted in small clusters.
Buy: barrettsbridge.co.uk, £17.34
Autumn moor grass (Sesleria autumnalis)
With white, caterpillar-like plumes in summer, this loosely formed moor grass makes a fantastic ground cover plant in dappled shade.
Buy: macplants.co.uk, £7
Wood melick (Melica uniflora)
Much like hakonechloa, melick is a dream underplant. Its fine flower buds, appearing in early summer, are like raindrops in motion; its foliage is lushly clumped. Plant in groups.
Buy: bethchatto.co.uk, £8.50
Gossamer grass (Anemanthele lessoniana)
Also known as pheasant’s tail grass or wind grass, A. lessoniana morphs in the later months from light green to every shade of autumn – all oranges and ochres. Reaching a metre tall, it is best planted in drifts or dotted through a border.
Buy: claireaustin-hardyplants.co.uk, £8.50
