In Japan, they have a word for it – momijigari. This custom of observing the trees changing colour in autumn might not be quite so formally recognised in Scotland, but it's equally well loved. As crisp, clear days arrive, many of us are filled wit
h an irresistible desire to take a walk through woodlands that have been transformed from green into a blaze of yellows and reds. Dogs and small children go rushing off through the fallen leaves and keen photographers are spoilt for choice. The Forestry Commission has even created a colour chart on its website (www.forestry.gov.uk) so you can check from day to day to see what colour the leaves are at your local woodland.
And this riot of colour isn't just confined to wild spaces – from the grounds of historic homes to small suburban plots, gardens are also displaying the best the season has to offer.
At the National Trust's Crathes Castle in Aberdeenshire, head gardener Callum Pirnie says he has seen some particularly interesting plant combinations in autumn over the last two or three years. "Climate shift has an impact," he says. "One of the interesting things we're seeing is that the season is getting longer. So you get a great combination of the late summer and early autumn flowers with the autumn colour of the trees and shrubs."
At Crathes this means late-flowering daisies such as heleniums, possibly some dahlias if there hasn't been a frost, kniphofias (red hot pokers), penstemons, nerines, blue spires of aconitums and several other flowering plants that can still be holding their colour well into autumn.
Another popular garden plant known for looking good at this time of year is the sedum, especially Sedum "Autumn Joy" with its mass of salmon pink flowers which deepen to a rich burgundy and later turn to seed, providing winter interest. Many of the mop-head hydrangeas offer a long season of interest too, changing colour to browns and bronzes that last most of the winter. For example, Hydrangea x preziosa is well known for its reddish-brown stems and bronze-red flowers.
Although most of us associate trees with autumn colour, there are a huge range of shrubs which also put on a good show. The dark purple foliage of Cotinus coggygria "Royal Purple", also known as the smoke bush, is a popular garden shrub year-round, with tiny pink-purple flowers in summer, and in autumn its leaves turn a vibrant orange. Corylus maxima "Purpurea" is another shrub that offers good value – with deep foliage, it produces edible nuts in autumn and purple catkins in winter. The witch hazel, Hamamelis x inter-media, is another dramatic choice, and you can find cultivars with yellow, orange or red flowers standing out against bare stems.
At Crathes Castle, one of the best autumn sights is an avenue of enkianthus – a slow-growing shrub whose colours range from red to orange to a touch of yellow. Even if you don't have room to recreate this effect on a grand scale, it's a shrub that can work well in any space. "Especially in a smaller garden, you should really always look at plants that give you two hits," he explains. "So with Enkianthus campanulatus, which is probably the most common one, you get delicate spring flowers coupled with tremendous autumn colour." Other shrubs he recommends include Fothergilla monticola and Eucryphia glutinosa, a deciduous plant from Chile, which has a display of huge white flowers in August and into September, followed by bronzy orange foliage. "It's a plant I always recommend to people," says Pirnie.
The basic science behind this colourful foliage centres on chlorophyll. The Forestry Commission's website describes leaves as "the food factory of the tree". Leaves use the moisture and nutrients sucked up by the roots and process these with air to produce sugars and starches, which allow the tree to grow. Sunlight is essential for the process and is trapped in the leaves by a green pigment called chlorophyll. When the days grow shorter and night temperatures fall, the food factory shuts down and the chlorophyll in the leaf decomposes. The pigments from the starches and sugars start to show, resulting in autumn colour. More specifically, pigments known as carotenoids give yellows and oranges, while anthocyanins give reds, blues and purples.
In Deeside, according to Callum Pirnie, some of the finest autumn sights are when the birch woods turn a vivid gold, with trees such as bird cherry turning bright red and then the aspens turning yellow. If you can't create this sort of New England-style scene in your own garden, it's worth choosing a special tree to act as a focal point. "I really do rate Japanese maples for smaller gardens," says Pirnie. "You can get quite big ones down to fairly dwarf sizes and there is such diversity of autumn colour in them – they are absolutely stunning."
If showy leaf colour isn't quite enough, you might want to consider some of the plants that produce interesting berries or even flowers in autumn. Viburnum bodnantense "Dawn" is a popular choice, thanks to the strongly-scented pink flowers that appear on bare branches in late autumn. In the berry stakes, cotoneasters have red berries which last over winter, as well as attractive flowers in early summer. Pyracanthas can be used to make a prickly hedge, with berries in yellow, orange or red.
"Euonymus planipes is amazing because it has a very showy fruit that opens out, so you get the vivid colour of the orange seed and then it goes a vivid autumn colour as well," says Pirnie. "Another one that a lot of people like is the mountain ash Sorbus "Joseph Rock", which again is a double hit because you've got autumn colour and yellow berries."
The choices are endless, but whatever plants you opt for, there's no reason why your garden can't be as colourful and striking in autumn as our native woodlands.
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www.vanmeuwen.com/scotsmanThe full article contains 1027 words and appears in The Scotsman newspaper.
