Similarly, when our terrain is at its drabbest, a chance encounter with a lone spectacular tree or shrub, or with a small but riotous assembly in a clump or hedgerow, can move me more than the landscapes entirely mantled in scarlet that I’ve visited overseas.īut there’s no escaping it: our wild autumn foliage colour tends to be patchy and piano by comparison with that of those other regions and all too often spoiled by temperamental weather. Multi coloured leaves on a Cotswold beech tree in autumn at Edge, Gloucestershire (Pic: Alamy) Personally, I’d prefer a mellow Buckinghamshire beech to New England’s fiery finest any bright autumn day. More prone to those factors, and so less consistent, are the wayfaring tree, briars, brambles, bilberry, alder buckthorn, ash, birch, hawthorn, blackthorn and apples both domestic and crab – not that they’re any less ravishing when at their best. These are reliably breathtaking, although their performance still depends on site, weather and genetic variability (in that some individuals or forms of a species colour better than others). Nonetheless, some of our native back-end beauties stood their ground or regained it, most notably beech, wild cherry, rowan, field maple, spindle, guelder rose and the dogwood Cornus sanguinea. Our flora was once rich in them, too, but their opportunities for refuge and return were vastly poorer. In North America and the Far East, a great diversity of species was able to migrate south to escape advancing ice sheets and then to reoccupy its old territory as the climate warmed again.Īmong these were the ancestors of today’s autumn exhibitionists.
Great Britain is not so favoured by accidents of history and geography as many other parts of the world. Why are many native British trees not as colourful as imported varieties? Their transition is so dependably glorious that it’s fixed in consciousness and calendar as a national natural event, inspiring mass celebratory excursions such as the ‘leaf-peeping’ tourism of the New England fall and the momijigari (‘maple hunts’) of the Japanese autumn. They’re also home to a multitude of native trees and shrubs that colour brilliantly. There are vast regions where this is the norm, notably in North America and North-East Asia. The optimum conditions are a lush growing season followed by an autumn that is dry, tranquil, warm and sunny by day and cool but not freezing by night. (Pic: Alamy) What are the best conditions for autumn colours to burst through? In cultivation, over-prolonged feeding and watering can wreck the show for the same reason.īrightly coloured Autumn leaves against a blue sky. New growth seldom colours so well as older and ripened branches. This encourages late growth and foliage that’s newly minted or still thrusting as autumn sets in. Scarcely more favourable is sustained wet weather in August and September. Stresses such as summer drought, impoverished or ill-suited soils and constricted roots cause leaves to turn and drop early. Damp gloom and drenching rain disrupt their change, dulling and diluting their hues, and making them prone to premature decay. Rough winds damage leaves and accelerate their decline and fall – or strip them outright.
Strong sunlight greatly enhances the production of anthocyanins, as do nighttime chills, but early frosts curtail it. What decides whether a leaf becomes red, yellow, orange, purple or some other colour?Īfter innate chemistry, environmental conditions are the main determiners of autumn leaf colour. Thereupon, their effects may blend with those of other pigments, making some of autumn’s most painterly tinctures: brackenish sepia and tortoiseshell, mushroomy buff and peach-tinted parchment, burnished copper and ferrous red, bitter chocolate and black cherry, caramelised bronze and honeyed old gold. However, tannins are also present in the growing season and they become evident as soon as the chlorophyll starts disappearing. Enduring after the other colours have faded and the leaf has transpired its last, these produce the browns that are the livery of death and decay. The final addition to the palette is tannins. Woodland path in autumn, Epping Forest (Pic: Alamy) Why do the leaves end up turning brown? Country Life's Top 100 architects, builders, designers and gardeners.
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