With little going on in the garden in winter, even the most subtle of events is cause for celebration, writes JANE POWERS.
ALTHOUGH IT'S JUST a few degrees above freezing, bumblebees are nuzzling the winter flowering cherry outside the window. The tree, which bears the unwieldy botanical name of Prunus x subhirtella'Autumnalis', blooms spasmodically from November until March. The books say it flowers only during mild spells, but in our climate it produces regular surges of papery blossom throughout the chilly months.
The flowers, which are very pink in the bud, and white or shell-pink when they open, are among the most dainty of all those borne by cherries. Their pale, frail loveliness combines with the dark, knobbly, bare branches to give a lean and perfect Japanese-print effect – which is exactly the kind of thing that looks best in these sparsely-flowered days of winter. Seen against a clear blue sky, the pink is exhilaratingly exaggerated; and even on a grey day the petals are like rose-tinged snowflakes.
If the winter cherry has one failing, it is that it has no scent. Nonetheless, it attracts plenty of pollinating bees, presumably by the highly visible abundance of its flowers. Another tree that is equally odourless, but which vies with the winter Prunusfor bare-branched, oriental-arty exquisiteness, is the Persian ironwood ( Parrotia persica). Its flowers lack petals, and are merely bundles of chunky, strawberry-red stamens, but they peep out of their dark-brown suede buds with painfully delicate hesitancy. In summer, of course, one wouldn't give such sheepish blossoms a second glance, but now, with so little going on in the garden, the most subtle of events is cause for celebration. (Winter, I'm afraid, transforms us gardeners into somewhat tiresome aesthetes.) For autumn colour, however, it's difficult to find a greater show-off than Parrotia: its changing leaves range from deepest maroon, to fire-engine-red, to flaming orange and yellow.
Winter jasmine ( Jasminum nudiflorum), again scentless, and again flowering on bare wood, is another simple little poem of a cold-weather bloomer. The six-petalled, lemon flowers are held close to the dark green stems, where they open sparsely, like a scattering of acid-yellow stars in the darkness of winter. Unlike its perfumed relatives, this jasmine is not a climber. It is more a leaner, so it still needs the support of a wall or an arch. Left to its own devices, it becomes a tangle of whippy growth, looping through itself and other plants. To avoid this, it should be pruned after it finishes flowering in late February or early March. Snip the flowering stems back to about three pairs of buds from the main stem.
Before we consider the heady matter of scented winter plants, let me recommend one other fragrance-free shrubby specimen. The aptly-named silk-tassel bush ( Garrya elliptica) is an evergreen that covers itself with long greenish catkins that dangle weightily, like an overblown Victorian upholstery project. It is in flower from mid-winter to mid-spring. The variety 'Pat Ballard' has wine-tinged tassels, while those of 'James Roof' are silvery grey.
Shrubs that bloom in winter include some of the most powerful fragrance-makers. The mighty odour they send into the chill air acts as a message to the few pollinating insects that are active at this time. The scent sends an “open for business” signal to the insect, which, all going according to plan, comes along to collect nectar or other food, and unknowingly transfers pollen to another flower of the same species.
The top perfume producers are the Daphnegenus. The evergreen D. bholua'Jacqueline Postill' is one of the more available (and more scented) varieties. It is a seedling of the deciduous 'Gurkha'. Both are in flower at this time of the year, with little clusters of pinky-white trumpets. Daphnes, apparently, are poisonous if you eat them. I can't imagine why you would – but I'll pass the information along anyway, as a complimentary health and safety notice. Of more interest is that they can be difficult to grow, and have a propensity for dying without any good reason. I've killed a couple in my day, and have since given up on them: I can't supply the humus-rich, moisture-retaining (but not water-logged) soil in a sunny position that they require to thrive.
Viburnums are less fussy, and the hyacinth-scented cultivar V. x bodnantense'Dawn' is available in many garden centres. It starts to flower in autumn, when the shrub is still in leaf, and it goes on into early spring, gradually losing its leaves, until the bundles of little pink tubes are held on starkly naked stems. It looks best in this unclothed state, as the flowers have a touching vulnerability.
Another bare-wood bloomer is wintersweet ( Chimonanthus praecox) with spicy-smelling, wine-stained yellow flowers that have an odd, glassy appearance. The form 'Grandiflorus', has, as the name suggests, larger flowers than the species. Wintersweet isn't in a hurry to flower, so you may be waiting some years for the first blossoming episode. It will flower better, and possibly more quickly, if grown against a warm wall. Pruning is not recommended during the waiting period, as it may postpone production of blooms. After its virgin flight of flowers, however, you can prune annually in spring, but don't go mad with the secateurs. Just remove badly placed or damaged stems, and shorten the gangly bits.
The witch hazels (Hamamelis species and cultivars) also bear their strange, spidery, crepe-paper flowers on nude stems. The yellow varieties are more scented, with H. x intermedia'Pallida' supposed to be the most pungent. But the reddish and orange flowers of kinds such as 'Jelena' and 'Diane' offer a glowing-ember colour not often seen at this time of the year. Witch hazels appreciate a deep fertile soil, so if yours is not naturally so, add plenty of organic matter to the planting hole, and give an annual mulch of leaf mould or garden compost.
A plant that is much esteemed for its winter aroma is the glossy, evergreen Christmas box ( Sarcococca confusaand S. humilis). The white or pink-tinged (in the case of S. humilis) flowers are like tiny short shreds of string, but they pack a powerful punch to the nose. My nose, I have to admit, doesn't like the smell at all, as it reminds me of too much talcum powder masking something unpleasant. However, I've never met anyone else who feels the same, so my sense of smell may be marching to its own tune.