Autumn leaves

GARDENS: The Indian summer has brought a riot of colour to the garden

I FEEL THE tiniest bit sheepish that a month ago I was complaining about the darkening days and end-of-season decrepitude in the garden. Misery was all mine. The third consecutive non-summer had worked its soggy spell on my psyche, and I was deeply enmired in the slough of despond. And then, along came September: golden, warm and festive. The month was like winning a holiday jackpot – especially for those of us who had not been out of the country. In plants too, the sunny days provoked an unexpected revival. Cells that had started to shut down and shrink were suddenly coerced open and pumped up by the surprising heat.

The Indian summer also gave trees and shrubs a shot of the warmth that manufactures sugars in their foliage: sugars that in their turn produce anthocyanins, the heart-lifting reds, crimsons and purples of autumn. Crisp, cold nights help to seal the veins of the leaves, and prevent the colour-creating sugars from leaking away. As I’m writing this, the leaves are starting to turn, and are looking promising for a blazing season. The yellow and peachy tones (xanthophylls and carotenoids respectively) are less dependent on weather. These pigments are already present in the tissues, and are gradually unmasked when the green chlorophyll breaks down at the end of the growing season. Even during a rainy, mushy year, the leaves will go yellow.

And indeed, yellow is a fine colour to have on the trees during these months. The first thing I see when I look out the window in the morning is a lanky birch jingling with golden leaves, and the grass at its feet scattered with amber snowflakes. This always sets me up for the day. Another flaxen-foliaged tree is the katsura ( Cercidiphyllum japonicum). In good years, its heart-shaped leaves become tinged with pink and orange, but even in the dreariest autumn they have a warm, buttery glow. This east Asian's performance is relatively short-lived, but it makes up for its brevity with another trick: it gives off a sweet smell of burnt sugar in September and October (and again in spring, ever so faintly).

Larches, which also turn a pretty mustard colour at this time, are oddities in the plant world. They are one of just a handful of deciduous conifers. The others are members of the cypress family and include the swamp cypress ( Taxodium distichum) and the dawn redwood (Metasequoia glyptstroboides) both of which become suffused with copper and orange. Ginkgo, which is sometimes classified as a conifer (but doesn't exactly conform to the description), dresses its curious leaves in lemony hues before dropping them.

Another tree with unorthodox leaves that fade to yellow is the tulip tree ( Liriodendron tulipifera). Its foliage looks a little like fig leaves with the ends sliced off. Fast-growing and eventually very big, it is suitable only for large gardens.

Some of the Japanese maples ( Acer japonicumand A. palmatum) also assume tasty custardy tones. These are much more manageable sizes, from a metre to several metres tall, depending on the variety. Red is the colour that we more often associate with these little trees in autumn. 'Osakazuki' is supposed to be the most dazzling.

In fact, reds, oranges and crimsons are the tones that we crave most in this season. They look their best in the low, end-of-year light. In high summer, reds can be problematic in full sun, and can be blinding rather than warming. But in the slanting October rays, these hot colours seem to come alive from within. And because there is little competition from flowers now, each autumn-ignited tree and shrub stands out like a welcoming beacon.

Among our native woody plants there are a handful that proffer vivid, ruddy tones: the mountain ash or rowan ( Sorbus aucuparia), bird cherry ( Prunus avium) and guelder rose ( Viburnum opulus). But we must look to north America and Asia for the liveliest of autumn leaf-changers.

America gives us stag's horn sumach ( Rhus typhina), one of the first to transform its leaves to carmine and scarlet. It has a bad reputation, as it can spread by suckers, but normal vigilance will keep these under control. Sumach stays smallish, and is often seen in front gardens.

If you can give it the space, the sweet gum ( Liquidambar styraciflua), from the eastern US, is possibly the best of all autumn flamers. It makes a huge pillar of vermilion, cherry and maroon foliage. The leaves stay on the tree for weeks, until Christmas even – if a winter wind doesn't whip them away earlier.

That great continent to our west also offers us the red oak ( Quercus rubra), the silver maple ( Acer saccharinum), tupelo ( Nyssa sylvatica), and several dogwoods ( Cornus) and viburnums.

Asia, meanwhile, gives us maples, dogwoods and viburnums, as well as many other autumn show-offs. The Persian ironwood ( Parrotia persica) is slow growing with multi-tinted leaves on long horizontal limbs (popular with our hens as perching spots). Disanthus cercidifolius, a shrub from Japan and southeast China, has heart-shaped leaves that flush to wine and crimson; it requires a lime-free soil. There are many Asian Sorbus species that produce vibrant cardinal tints at this time of the year.

And let's not forget the climbers: members of the Parthenocissus genus are among the most flamboyant. Virginia creeper ( P. quinquefolia) is from the United States, but the plant known as Boston ivy ( P. tricuspidata) is actually from east Asia.

PLANT FOR COLOUR

Blue leadwort ( Ceratostigma plumbaginoides): low, groundcover shrub with brilliant blue flowers and leaves that turn red and wine in autumn.

Smokebush ( Cotinus): fast-growing shrub with oval leaves that turn orange and red; excellent for dry soils; prune stems hard in spring for larger leaves and to control size (although you will lose the billowing, smoky inflorescences).

Euonymus: the foliage of our native spindle bush ( E. europaeus) takes on flaming red and orange tones (and gives us berries for the birds). 'Red Cascade' is a cultivated variety with an abundance of fruit. The Asian E. alatus, E. latifoliusand E. planipesalso put on a fiery act.

Witch hazel ( Hamamelis): most of these large shrubs go a warm yellow, while 'Diane' and 'Jelena' become an exuberant orange and red.

Fothergilla major: large shrub with white bottle-brush flowers in spring, good autumn colour, needs lime-free soil.

Vitis coignetiae: a climber with enormous hairy leaves that turn bright red. Needs room to clamber and scramble freely.