Pampas grasses, or Cortaderia, are large, tussock-forming perennial grasses that form striking specimens with their tall stems and flower plumes. But they have been unfortunately pigeonholed as a dated 1970s plant because of their ubiquitous use in suburban front gardens.
To compound matters, customers may not have fond memories of pampas grass because anyone who lived with one on the garden path would have suffered from injuries as they struggled past the razor-sharp foliage.
But pampas grass could be making a comeback. Last year, Nikki Davies of Oxfordshire-based Potting Shed Nurseries noted a distinct rise in sales among retail customers. There are smaller forms that are better suited to compact, modern gardens and Cortaderia can provide great structure in mixed borders or in grass gardens.
There are 24 species of Cortaderia but only four are grown in the UK. C. selloana, found in the Argentinian pampas from which it takes its common name, is the most widely grown, with many varieties. The species has glaucous, evergreen foliage with rough edges and flowers held well above. There is quite a range of varieties, differing in flower colour, leaf colour and height.
Then there are two New Zealand natives, C. fulvida and C. richardii. C. fulvida is slightly less hardy than C. selloana, coping with short-lived frosts down to -7 deg C but not -15 deg C, which C. selloana can tolerate if kept clear of wet conditions. It is earlier flowering than C. selloana, with flowers a hazy pink colour, fading to white. The flower panicles are branched and their extra weight makes the stems arch over the clump of light-green leaves.
C. richardii is arguably the most elegant of the species and the earliest to flower. But it is less hardy than C. selloana, needing protection in the coldest winters. It has dense, silvery plumes at the top of stems, which are very arching.
Plants like a sunny position in well-drained soil. They accumulate dead material in the centre of the tussock. The recommended method for getting rid of old growth is to put on gloves, comb through the plant and cut out the old leaves and stems. Some recommend cutting back the clump quite hard every spring to control the spread and promote new growth. However, C. richardii does not respond well to such treatment.
Plants can be male or female, with the female plants bearing the showiest flowers. They persist well into winter and look lovely rimmed with frost. The plumes can also be dried for flower arranging.
WHAT THE SPECIALISTS SAY
NIKKI DAVIES, co-owner, Potting Shed Nurseries, Oxfordshire - "Cortaderia is a very popular line that we grow and is a fantastic specimen feature plant. Last year, we sold a lot of the common pampas grass direct to our retail customers so it certainly looks like it's back in fashion.
"My favourite is a selloana type called 'Splendid Star', which has stunning bright yellow and green foliage and is a lot smaller growing, only reaching 60-70cm with white plumes in late summer. It grows very well in sun or semi shade and is perfect for customers with a smaller garden. We find them very easy to grow and to our knowledge they don't pick up any diseases easily."
DAVID ALLEN, owner, Meadowgate Nursery, West Sussex - "Cortaderia is actually the least popular of the grasses we grow, which has a lot to do with people's recollection of seeing them plonked in the middle of the lawn surrounded by heathers. Most varieties are too large for modern gardens.
"Having said that, they have their uses. They need full sun but are happy in most soils and once established are drought-tolerant, cold-hardy, do well on the coast and can be used as windbreaks.
"Our most popular variety is C. selloana 'Aureolineata', which is golden variegated and bears white plumes and works well in containers. We also grow C. richardii, which is tall at 3m and is good for waterside planting, and the compact C. selloana 'Pumila'.
NEIL LUCAS, owner, Knoll Gardens, Dorset - "While they can be used well, and they look stunning en masse, I think they still suffer in many people's eyes from misuse a good few years back. Admittedly, a lot were seed-raised, so these days as long as a cultivar is selected it overcomes the majority of objections.
"Most are sold as feature plants for accent and for this, C. selloana 'Pumila' is difficult to beat for its longevity and display. We like C. selloana 'Evita' for being compact and free flowering. C. richardii is high on my list of favourites because it is earlier to flower and far more graceful than its cousins."
PAULINE PRESTON AND DAVID AITKEN, owners, Wildly Rural, Cumbria - "Pampas grass is one of the true giants of the grass world. It's tremendously robust, yet extremely ornamental and looks fantastic planted naturalistically in well-spaced swathes over contoured earthworks, mounds and slopes, with appropriate companion planting, boulders, rocks and aggregate mulches.
"That kind of design needs minimal maintenance but provides maximum impact. We like the natural form of C. richardii, which fits in with our design style. When a smaller variety is more appropriate to the design, we go for 'Pumila'.
"The matted basal foliage of older plants is a favoured hibernation site for hedgehogs, so shouldn't be set alight. Use powered hedge cutters to cut close to the clump in late spring instead."
SPECIES AND VARIETIES
C. fulvida is a tall species with distinctive creamy-brown flower plumes. Easy to grow in a variety of locations. Frost-hardy.
C. richardii is perhaps the most ornamental of the pampas grasses, with tall, arching stems topped with gently nodding silvery flower heads above narrow, olive-green foliage. Looks particularly good next to water. Height: 2.5m.
C. selloana forms a dense clump of long glaucous to mid-green leaves. It grows virtually anywhere but is most vigorous in or beside a bog. Produces tall spikes of white flowers that can be tinged pink or purple. Hardy down to -15 degsC. Height: 2.5-3m. Spread: 1.5m.
C. selloana 'Albolineata' (formerly 'Silver Stripe') is a compact, slow-growing plant with white-margined leaves and silvery-white plumes. Hardy down to -15 degsC. Height and spread: 2m.
C. selloana 'Aureolineata' Award of Garden Merit (AGM) (H3) (formerly 'Gold Band') has variegated leaves with golden yellow margins. Height: 2m. Spread: 1.5m.
C. selloana 'Evita' PBR was selected for its compact, free-flowering habit. It produces mounds of green foliage topped by very short-stemmed, large, fluffy white flowers from midsummer onwards. Height: 1.5m-1.8m.
C. selloana 'Icalma' forms dense clumps of arching, mid-green leaves and tall stems of silky, creamy white plumes. Flowers from August to September. Height: 1.5m. Spread: 1.2m.
C. selloana 'Monstrosa' is the largest cultivar. It produces a gigantic mound of foliage and flower spikes up to 3m tall.
C. selloana 'Petite Plumes' is a choice form that has arching foliage with a subtle golden variegation and low-growing flower plumes. Excellent for smaller borders and pots and requires moist but well-drained soil.
C. selloana 'Pink Feather' forms dense clumps of arching mid-green leaves. It produces tall stems of silky, silvery plumes tinted pink in August and September. Height: 2.5-3m. Spread: 1.5m.
C. selloana 'Patagonia' is a recently introduced dwarf form that reaches 1.4m. It has steely grey foliage and warm buff flowers from July onwards.
C. selloana 'Pumila' AGM (H4) produces lots of handsome long-lasting flower heads in late summer. Copes well with an exposed location because it is stouter and more compact than other forms. Height: 1.5m.
C. selloana 'Rendatleri' is a tall form of pampas grass that bears pink flowers. Hardy down to -15 degsC. Height and spread: 2.5m.
C. selloana 'Rosea' produces its tall pink plumes from August to November, with the flower heads persisting throughout the winter. Height: 180cm.
C. selloana 'Silver Comet' has an upright, dense habit. Its large white feathery plumes appear in late summer and last into winter. Foliage is narrow and grey-white with silver margins. Height: 1.5m. Spread: 1m.
C. selloana Silver Feather = 'Notcort' makes an ideal garden specimen because it is compact and elegant, slightly smaller than most, reaching 2m in height. It has slender foliage with silver variegation. Its pale flower stems with silky cream plumes emerge in early September and will often last into February.
C. selloana 'Splendid Star' PBR has long, arching, green and yellow variegated foliage. Its elegant, cream flower plumes rise high over the foliage in late summer and autumn.
C. selloana 'Sunningdale Silver' AGM (H3) forms dense clumps of arching mid-green leaves and tall stems bearing weather-resistant, silky-white plumes. Height: 3m. Spread: 2.5m.
C. selloana 'White Feather' produces spectacular tall silver-white plumes, making it an ideal specimen plant. Height: 180cm.