Cool and calming; grasses are here to stay – by Neil Lucas of Knoll gardens
Easy to use….. easy to please
Gardening, like many other pastimes has its fashions, new or ‘re-discovered’ plants come and go all the time but every now and again a plant or group of plants comes along that opens our eyes to previously unthought of possibilities. This must surely apply to ornamental grasses. When I first came to Knoll we probably grew five or six and yet now we have over six hundred, with something of a reputation for our specialism.
The reason for such an increase in popularity is the immense range of shape, form, colour, habit and flower that grasses offer. Because they are so different from the usual range of plants grasses are excellent for creating excitement and interest in the garden border. The very nature of their structure allows their stems and flowers to move in the wind and so create movement in the planting as a whole, something which is so often lacking in the average garden border.
Not only are grasses very beautiful plants individually, together their strong linear line and texture can help bring a satisfying overall shape and form to our gardens design. They create movement, because stems and leaves sway in the slightest wind. They are durable, tough, and hardy. They are easy to use, and they are easy to please.
They are also very tactile; or to use a technical horticultural term, they are very ‘touchy feely’. Take for example the ever popular pony tails grass, Stipa tenuissima, with its narrow bright evergreen hair like foliage moving with the slightest breeze, it just calls out to be stroked!
At Chelsea Flower show, as with most other shows, there is a general understanding that plants on individual exhibits are not to be touched. On our stand we have all but given up insisting on this etiquette as it seems to be an instinctive reaction on the part of visitors to our stand to want to run their fingers through the grasses foliage. After all, gardening is about delighting the senses; be it sight, sound, smell, taste, or touch. So I have come to believe that anything creating such a positive reaction should be encouraged.
From a gardeners viewpoint there are two basic groups of grasses. The evergreens, which maintain their foliage year round; and the deciduous types, which go dormant for the winter re-shooting from the base with fresh new growth each year. Botanically the relationships are more complicated, but these botanical distinctions need not overly concern the gardener.
Wow factor grasses
Nearly all of the wow factor grasses; those often tall willowy plants with masses of flower swaying in the slightest breeze are deciduous plants which prefer sunny open positions to do best.
But don’t let the thought of dormancy put you off as, although the grass goes dormant, in other words growth goes from green to brown, the stems, leaves and flowers remain mostly intact all winter long, emphasising the beauty of the plant and the changing of the seasons. Winter sunshine reflecting on frosted grass stems on a crisp winters morning is a most beautiful sight.
In early spring simply cut them down to the ground, and come July they will start to flower again. The rate of growth, especially amongst the taller varieties, really is one of nature’s annual miracles
For example the miscanthus are unequalled for planting in borders where a bit of height (2metres approx) is needed and there are many to choose from. Miscanthus ‘Ferner Osten’ is one of the very best producing literally hundreds of amazing dark red flowers in high summer. The effect is simply stunning. Miscanthus Cosmopolitan has brightly variegated white and green leaves which will take a little more shade though like most variegated plants doesn’t produce much flower. Miscanthus ‘Yaku Dwarf’ as its name suggests, is rather shorter and covers itself in flower for the second half of the year.
If the miscanthus are a little large then why not try some Panicums; upright mounds of blue or green foliage covered with masses of tiny flowers that effervesce together creating a cloud like impression through which you can grow other larger perennial flowers like the Echinacea or cone flower. Two favourites are Panicum Shenandoah and Panicum Warrior, both of which have foliage turning red tinted later in the summer.
The fountain grasses, or Pennisetums are aptly named as although they start rather late in the year compared to many plants they produce spectacular quantities of fluffy catkin like flowers that are great towards the front of a border. There are many to choose from; Pennisetum Hameln comes highly recommended for its regular profusion of flower.
The deciduous grasses, are well known for their wow factor effect in full flower; while the evergreens are often regarded as less showy, generally smaller growing, and used primarily for their wonderful foliage rather than flower power.
As a general rule evergreens will also take more shade and damp than the deciduous tribe.
Anemanthele lessoniana (terrible name, wonderful plant), has richly coloured mounds of foliage that will tolerate the driest of shade.
Many of the smaller sedges, or Carex, make wonderful compact mounds of foliage such as Carex Evergold with its brightly cream and white striped leaves is also excellent for containers. From New Zealand, Uncinia rubra forms tidy mounds of deep reddish foliage that is always striking.
Another carex, Carex testacea has beautiful narrow foliage that at times take on an almost burnt orange colouration. There are many to choose from.
However evergreens are not without their large show stoppers; the quite fantastic Spanish Oat Grass, Stipa gigantea has the most effective tall golden oat coloured flowerheads arising from fairly ordinary clumps of narrow tough green leaves. Uncompromising in its demand for full sun and well drained soils, an established plant is an object of long lasting beauty. It also has a ‘see though’ or transparent quality, which means that although it is 2 metres tall, most of this height is made up of comparatively narrow stems so that it can be used towards the front of a border or in small spaces where you would not necessarily consider a 6 foot giant might fit!
This article kindly supplied by Neil Lucas of Knoll Gardens