'Elephant grass' isn't just an alternative fuel crop - it could also look great in your garden. Jane Powers on the beauty of late-season grasses
October belongs to the ornamental grasses. When much else in the garden is winding down or withering, the noble grass tribe is just coming into its own, lording over the other vegetation with its grainy, tawny flower heads.
Yeah . . . grass . . . say the cynics: grass is grass, and there's not a lot to say about it. Oh, but I have to protest, that's because you're not looking at it - as it catches and elaborates the autumn light in its clusters of seed heads. Or even listening to it, swishing in the breeze like waves on the seashore. Or feeling it, tickling the back of your neck as you duck through a border.
I'm not talking about the more squat, more restrained grasses that flower earlier in the season, such as the Festuca (fescue) and Carex (sedge) species. Many of these are like vegetable hair-dos, either spiky or flowing (there are even sedges called 'Frosted Curls' and 'The Beatles'; and a fescue named 'Golden Toupee'). And while these coiffures make excellent groundcover, pot-fillers and decorative blobs for gravel gardens, they lack the flair and drama of the late season grasses.
The late bloomers that I'm concerned with here are the ballet dancers of the grass family. They're graceful performers with flower heads arching downwards, stretching skywards, or puffing gently outwards - such as Calamagrostis, Molinia (purple moor grass), Panicum (switch grass), and Pennisetum species. And of course, they include the king of all ornamental grasses, mighty ruler of the autumn border and emperor of the entire Poaceae family, the incomparable Miscanthus.
This largely Asian genus has been in the news recently because research has proved that the hybrid Miscanthus x giganteus can be grown in many places (including Ireland) and used successfully as a biomass fuel crop. If 10 per cent of our arable land was planted with the grass, "we could generate 30 per cent of our electricity requirement" claims Trinity College Dublin botanist Mike Jones, according to an article in this paper last month.
The so-called "elephant grass", which can grow to three metres, is a cross between M. sacchariflorus and M. sinensis. The first of the parents is virtually indistinguishable from its gigantic offspring: together, it and elephant grass make a lofty non-flowering mass of broad leaves, a good green screen for the back of the border - if you have a border wide enough to accommodate their bulk. But when they do flower - in hotter climates - M. x giganteus is sterile, meaning it won't seed about beyond its allotted area.
But it is the other parent, M. sinensis, that has given rise to more beautiful cultivars than any other grass (nearly 100 varieties are listed in the current Plant Finder). Many of these have been introduced by the great German plantsman, Ernst Pagels, at his nursery in Leer in the northwest corner of the country. In the mid-1980s, Wolfgang Oehme (half of the famous American design duo, Oehme and Van Sweden) visited Pagels's nursery, and was bowled over by the elegant and showy grasses with their feathery inflorescences. Soon these Miscanthus (among them the wine-plumed 'Malepartus' and 'Rotsilber'), along with other flamboyant grasses, were forming the backbones of their prairie-esque "New American Garden" planting schemes.
Around the same time, German and Dutch designers were sending grasses drifting and waving through their landscapes. Now, at last, they are making regular appearances in our domestic gardens. And about time, because not only do they bring a moving, shining, tickling presence to a plot, they also extend the season by several months.
One of the earliest Miscanthus sinensis cultivars to flower, starting in late July or early August, is Pagels's 'Ferner Osten', with ruby-coloured plumes that fade to beige, and good orange autumn colour. Among the latest, flowering in early November, is 'Strictus', which has stiff leaves horizontally banded with gold. In between are dozens of others - and almost all have hard-wearing plumes that last well into winter. In upland and midland areas with sharp hoar frosts, Miscanthus and other tall grasses are frozen into crisp, silver-furred statues.
Jimi Blake, who grows 100 or more Miscanthus varieties at Hunting Brook Gardens in Co Wicklow, says that the tall 'Roland' is one of the best, with broad foliage and numerous flowers, that open out beautifully pink and crinkled.
The Calamagrostis genus also gives long-lasting seed heads, from the rusty, upright sheaves of C. varia and 'Karl Foerster', to the droopy, buff, ostrich feathers of C. emodensis, and the pink-tinged, relaxed tails of C. arundinacea (formerly known as Stipa arundinacea).
Molinia caerulea and Panicum virgatum and their many varieties have inflorescences of barely-there delicacy, the seed heads like tiny pearls strung on the finest of wires. The former originates from European and Asian moorland, while the latter is an American prairie grass, and does best in an open position with lots of air and light.
The flowers of Pennisetum take many shapes: those of P. orientale, P. alepecuroides and P. villosum form short, soft and furry tails, while P. macrourum has longer cat tails covered in a harder fur. But the most remarkable is the recently introduced P. glaucum 'Purple Majesty', a tender perennial developed at the University of Nebraska. It has near-black, strappy foliage and dark maroon bulrush-type flowers. Its rather stiff habit makes it better suited to pot culture, or a more formal setting than the other grasses mentioned here.
There are many more grass species that will enliven the autumn and winter garden: two to mention are Stipa gigantea (giant oats) and a lightweight pampas grass from New Zealand, Cortaderia richardii. These and countless other waving, light-catching, murmuring specimens are guaranteed to lift the Poaceae family out of the "oh yeah . . . grasses" category.