Gardening with grasses

Do your borders lack colour, height and movement throughout the year? Professional garden designer Nic Wilson of dogwooddays recently redesigned the beds in her own back garden to striking effect. Her secret weapon? Grasses.

By integrating their elegant structure and interesting foliage she’s transformed her family’s outside space. Here are Nic’s favourite grasses, where to plant them, and how to make them sing…

Are ornamental grasses easy to grow?

I particularly appreciate the versatility of grasses in a design – they can be used in so many different ways, aspects and situations. You can sow them from seed or buy them as plants for more instant results. Just choose the right grass for your border and watch them thrive.

When I changed my beds earlier this year, I decided to use grasses as the structural basis of the new design. I planted elegant Deschampsia cespitosa towards the back for height, drifts of Stipa tenuissima through the centre to create sinuous curves, and annual grasses like Briza maxima along the front.

Now it’s early September, the deschampsia has developed golden seedheads that mingle beautifully with my Verbena bonariensis, and the briza heads are gently rippling in the light autumn breeze. The yellow and oaty brown shades soften the brighter tones – a contrasting purple and orange colour scheme that includes:

• Copper Calendula ‘Sherbert Fizz’
• The subtly shifting coral, lime and claret of Rudbeckia ‘Savannah Mixed’
• Russet Helenium ‘Waltraut’
• Vivid orange Geum ‘Totally Tangerine’ 
• Cool purple Aster x frikartii ‘Mönch’

The best grasses for sun

Whether your garden is baked by the sun throughout the day or has shady areas under trees where little will grow, there are grasses that will cope. For sunny borders and hot, dry gravel gardens, little can beat Festuca glauca with its mound-forming blue-green spiky foliage. My festuca was grown from seed and I love to combine it with silvery lambs’ ears (Stachys byzantina) and purple salvia (such as Salvia nemorosa ‘Caradonna’) which also thrive in these baking conditions.

Carex testacea is a stalwart in my gravel garden as, unlike many varieties of carex, it prefers dry conditions and the foliage turns the brightest copper colour in full sun. It combines well with Kniphofia ‘Tawny King’ and Achillea ‘Terracotta’.

The best grasses for shade

At the other end of the spectrum, Anemanthele lessoniana prefers dry soils in sun or shade. Ophiopogon planiscapus ‘Nigrescens’ also copes with dry shade and Melica uniflora ‘Alba’ (or wood melic) thrives at the dappled edge of the woodland canopy.

Damp partial shade creates the ideal conditions for carex and acorus. I tend to favour Acorus gramineus ‘Ogon’ for its golden yellow variegated leaves and Carex oshimensis ‘Everest’, whose evergreen, white and dark green, variegated foliage makes a real statement in your border.

Annual grasses

Sowing annual grasses is an inexpensive way to add interest to beds and borders, or create attractive container displays.

I love the tactile flowerheads and deep chocolate-purple foliage of Pennisetum glaucum ‘Purple Majesty’ which looks splendid in autumn containers as a backdrop to dahlia and salvia. Another favourite, Briza maxima, is easily raised from seed in situ in the border. Autumn sowings work well and should grow on strongly the following spring.

Grasses for screens

Taller grasses make attractive screens to separate different parts of the garden or to hide utility areas. Try Calamagrostis x acutiflora ‘Karl Foerster’ which forms an informal screen up to 1.8 metres in height, with arching reddish stems fading through beige to warm browns as the season progresses. Calamagrostis looks fabulous in the winter too and can be cut to the ground in early spring before growth resumes for the next year.

Another tall specimen, Miscanthus sinensis ‘Silberfeder’, is topped with silver plumes of flowers in September and October which persist throughout the winter, adding texture and interest.

For slightly lower screens, I have two favourites. Pennisetum alopecuroides ‘Hameln Gold’ is a great choice with vivid yellow-gold foliage. Looking for something a little more exotic? Try the flowered plumes of Miscanthus sinensis ‘Zebrinus’. They grow to 1.2m in height, floating above striking bright green leaves striped with horizontal cream bands.

How to plant grasses

Perennial grasses are best planted in spring or autumn. Those that originate from warmer climates like miscanthus and pennisetum should be planted in late spring so they can come into growth before flowering in mid-summer. Deschampsia, stipa and festuca, on the other hand, originate from cooler climates and are better planted in autumn to give them the chance to become well established before beginning to grow in late winter.

As we head into autumn, September is the ideal time to plant the following grasses alongside your crocus and snowdrop bulbs:

• Tufted hair grass (Deschampsia cespitosa)
• Mexican feather grass (Stipa tenuissima)
• Ophiopogon planiscapus ‘Nigrescens’ – perfect for winter containers
• Carex oshimensis ‘Evergold’ – perfect for winter containers

Ornamental grasses add colour, structure, texture and all year round interest to beds and borders. But they really come into their own in the late autumn sun – the best time to enjoy their gently fading colours and elegant forms. Find more growing advice and helpful gardening tips in our dedicated grasses hub page.