Gill Heavens appreciates the sheer joys of planting for scent in the garden and the joy they bring to the senses.
This is a subject I do not claim to be an expert on. My sense of smell is on occasion non-existent, seldom efficient. I have often felt bereft as others have coo-ed and swooned whilst burying their faces into peonies and rhododendron flowers.
However in this perfume desert there have been noticeable oases, times when I could appreciate the joys and occasional horrors of scent in the garden.
So although some of these musings might be hearsay, I am happy to report that plenty has been often blissfully experienced for myself.
The scientific name for our sense of smell is olfaction.
For those of you so inclined the mechanics are along these lines. Chemicals in the air bind to specialised receptors located inside our noses. We have hundreds of these receptors, sensitive to as many different scents. These in turn send messages to our brain which very cleverly interprets them. People who have no sense of smell at all are known to have anosmia.
Roses are to many the quintessential perfumed garden plant, a rose without scent seems an anathema. However it is a question of personal preference; some fly the flag for sweet peas, lily of the valley or lilac. As scent has the power of recollection, favourites are often evocative of days past or childhood memories.
Perfumiers over the centuries have drawn on these traits to mix and match and reproduce facsimiles of our gardens. You can however have too much of a good thing. Some people find lilies over-bearing and the heavy bouquet of hyacinths can be cloying.
Quite naturally we seek out plants that smell delicious. These aromatic beauties are especially welcome in the winter months, including the delicious daphnes, wintersweet and Viburnum bodnantense. It is necessary for these shrubs to “shout” a little louder at this time of year, as pollinators are few and may need to be drawn from afar. This ‘turning up of the volume’ is to our advantage, and little can beat the joy of these glorious scents on a gloomy winter’s day.
Of course flowers are not pumping out fragrance to keep us silly humans enthralled, it is no selfless act of philanthropy. They are trying to attract pollinators. Just who these pollinators are is indicative of what scent evolved and when it is produced. It might be musky and fruity for beetles, sweet for bees and we all know what flies are attracted to!
Flowers that bloom in the wee small hours tend to be moth or even bat pollinated. Position the “nightshift”, whose members include nicotiana, tuberose and honeysuckle, close to evening seating areas to fully appreciate their fragrant offerings.
It is not just flowers that deliver delicious scent in the garden. Leaves are a little more reticent but just as valuable. With just a passing rub, volatile oils are released from herbs such as rosemary and pineapple sage, spearmint and lavender. Roots also can have their own particular scent. The rhizomatous roots of Iris germanica and Iris pallida are used to produce orris, a highly sought after ingredient in the perfume industry.
Some of our most beautiful border specimens have fragrance of dubious merit, including the Imperial fritillaries (Fritillaria imperialis), whose odour strongly resembles that of a fox. Although not especially agreeable to the gardener, it works well for the plant, dissuading the attention of nibbling mice and the like. Now it just has to work out something to repel the lily beetles!
They say “it is all in the name”. In the case of the shrub coprosma, which means “smells like dung”, it is quite true. When the leaves of some of these species are crushed it omits a rather unpleasant odour. The Antipodean is worth the risk, the evergreen foliage comes in a rainbow of colours, making it worthy garden member. Other stinkers include the dramatic and fetid foliaged Melianthus major, and the stunning Salvia confertifolia, whose leaves are described curiously as either “like meat” or peanut butter.
These strong smells act as natural defences against being consumed, and quite frankly I have no desire to even attempt a nibble of any one of them!
All of these pale into insignificance when you come to some of the plants which are pollinated by scavenging beetles and flies. Amorphophallus titanum, the Titan Arum, has a 3m floral inflorescence which opens slowly from late afternoon into the night to attract carrion loving insects. The Indonesian Rafflesia arnoldii, the corpse flower, has the largest and perhaps most rancid flower of them all at 1m in diameter.
Things that are good for the garden are not always fragrant, an obvious example being manure. The highly nutritious fertiliser “teas” of both comfrey and nettle are noxious, but certainly worth the discomfort for the benefits they contribute to the garden.
Let us not dwell on foul smells, after all that is not what we strive for in our gardens. Every season there is a fresh fragrance to look forward to. In winter we have the winter box, next we have spring bluebells, then summer phlox and in the autumn the candy floss scented leaves of Cerciphyllum japonicum. Each and every one of these enhances our garden experience, adding another dimension. The smell of freshly mown grass, even the bare soil on a sunny day, they lift our spirits and warm our hearts.