The grass is not always greener...
Ornamental varieties will excel in autumn as foliage and plumes put on a colourful display
AFEW years ago I made an early-autumn pilgrimage to the world-renowned Bressingham Gardens with the sole purpose of admiring its celebrated displays of late-flowering perennials. The seasonal bloomers on show certainly didn’t disappoint, but I wasn’t expecting to be blown away by its collection of ornamental grasses.
The beds in the Norfolk garden were crammed with calamagrostis, miscanthus, pennisetum and a host of other gems. In some parts of the garden they provided height, texture and structure alongside perennials, and in other places they were planted in bold swathes that delivered real drama.
Many of the varieties I saw that day offer close to all-year-round interest, but they really excel at this time of year when topped with fluffy flowerheads that turn into seed heads. Later in autumn, as temperatures nosedive, the foliage of deciduous types often turn shades of yellow, orange and red.
I should also mention that ornamental grasses are a benefit to wildlife. Ladybirds and other insects will take winter shelter in their flowers, while clumps of foliage provide cover for small mammals. Hungry birds will snaffle seeds from spent flower heads and gather wispy material to make nests.
Apart from being at their best in autumn, now is the perfect time to plant ornamental grasses. Snap up established plants and they’ll add some instant impact to your plot, while the roots of younger specimens will establish readily in warm, moist soil, enabling them to put on a cracking display next year.
ORNAMENTAL grasses is the generic term used to describe a large group of different species that originate from North America, East Asia, Africa and Europe, including Britain.
Breeding work on these wild plants has produced thousands of varieties, ranging from compact gems to those with plumes held on 10ft tall stems.
I’ve no doubt the most popular ornamental grasses are miscanthus, a group of evergreen and deciduous wonders that are native to China, Japan and the Korean peninsula. They turn heads with their amazing, feathery plumes in shades of white, silver, pink, red or purple, that rise above robust clumps of arching foliage. The first wild species arrived here in the 1870s but the range was limited until the end of the 20th Century, when German breeder Ernst Pagels introduced 50 super varieties, including ‘Flamingo’, ‘Kaskade’ and ‘Rotsilber’. According to the RHS Plant Finder guide, there are now more than 200 available in the UK.
Commonly known as fountain grasses, pennisetums grow wild in the tropics and sub-tropics. Breeding has given us 60 varieties with long-lasting tactile flowers that appear in late summer. The fuzzy plumes come in shades of white, pink, red, green, brown and purple.
Among the best are Pennisetum villosum with its caterpillar-shaped white flowers and P. alopecuroides ‘Red Head’, whose 10in-long by 3inwide red blooms are carried 3ft above the ground. P. orientale ‘Karley Rose’ forms a mound of light green leaves beneath slender 3ft stalks carrying fluffy rose-pink flowers. There are plenty of other autumnal wonders, including Calamagrostis ‘Karl Foerster’, Anemanthele lessoniana and Molinia caerulea subsp. caerulea ‘Variegata’, a striking form of a British native. Cortaderia fulvida is a wellbehaved pampas grass with silvery plumes that can reach 6ft or more.
Most grasses prefer a sunny spot and fairly fertile, well-drained soil – plants are likely to rot if they sit in soggy soil over winter. Taller ones make great focal points or backdrops for late-flowering perennials, while medium-sized varieties will make an impact when planted in groups within beds and borders.
Diminutive ones, such as Miscanthus sinensis ‘Yakushima Dwarf’ and Pennisetum alopecuroides ‘Little Bunny’, are ideal in pots. Start them off in 12in containers filled with a mixture of multi-purpose compost and soilbased John Innes compost. Grasses in pots are prone to drying out, so ensure they are kept moist.
Looking after ornamental grasses is easy. Unless they collapse during poor weather, cut back deciduous ones in late winter or early spring before new growth emerges. Tidy up evergreen varieties by snipping damaged foliage. Finish by spreading a 2in mulch around plants.
In time, grasses will spread slowly to form large clumps. Keep plants healthy, vigorous and within their allotted space by lifting and dividing every four to five years. Prise from the ground in spring and split into several decent sized, smaller pieces, discarding any dead bits. Replant a portion in the plant’s original position.