Gardening is a very sensual activity and it engages all of our senses. Our vision is continually excited by the changing forms, textures and colours. Our ears are alerted by the chattering of birds in the hedgerows or the sound of wind rustling through the leaves. Our instincts urge us to reach down and feel the ‘fur’ of the leaf covered in tiny, downy hairs or run our fingers through tussocks of soft grass. Our tastebuds are teased with the flavour of fresh strawberries warmed in the sun. For myself, the smell of a rose in bloom will always remind me of the warmest days of summer.
Gardens are full of scents, some pleasant, and others less so. Sweet peas have to be one of my favourites. Just a small bunch of the strongest varieties can easily fill a room with their delicate perfume, evoking memories of early summer. One of the best is the pink-picoteed ‘High-scent’, though the bi-coloured ‘Cupani’ and ‘Matucana’ are also very potent.
Jasmine also has an impressive fragrance. The winter flowering types will struggle to put out much scent in the cold days of January, but the summer flowering types, like ‘officinale’, produce a beautifully delicate aroma late in the evening. The chemical responsible (methyl jasmonate) is also thought to help protect plants from attack.
The shrub Philadelphus also has an incredible scent. It’s white flowers open during June and can often be smelt from quite a distance away. It’s bouquet has been likened to orange blossom and it is, in my opinion, one of the best shrubs for scent in Summer.
There are also lots of shrubs that have scented flowers in winter like the Viburnums, Witch Hazel, Mahonia or Sarcococca. They have to work very hard to spread the news of their flowers far and wide so they can draw in any pollinators bold enough to brave the cold at that time of the year.
It is not just flowers that fill the gardens with scent. I also enjoy the ‘fresh’ smell that comes from pine prunings, the scent of freshly mown grass and I have even been known, on the odd occasion, to savour the deep, earthy odour of a well-rotten compost heap.
There are of course, some scents which I would like to be able to avoid. I am always wary of the ‘almond’ smell given off by fresh clippings from a cherry laurel hedge as they start to release cyanide. The whiff of the dark anaerobic sludge from the bottom of the pond seems to soak into everything when I have to remove the pond weed and the foetid stench of a compost bin, after its contents have been ‘cooking’ for a week, can turn my stomach from 30 paces.
The aroma of some plants can be a clue to their properties. The intoxicating perfume of elder flowers is a sign of their sleep inducing power. There is an old tale which states never to fall asleep under an elder tree, or you won’t wake up. I haven’t ever fallen asleep under an elder, but only recently I was struck by the scent from an avenue of silver lime trees in full bloom. This late flowering tree produced a nectar so potent any bee partaking of it was knocked unconscious and you had to tread carefully to avoid stepping on all the ‘sleeping’ bees.
When using scented plants in the garden, we must consider their potency. Smells can travel some distance, so a garden filled with lots of different scented flowers can, rather than being a pleasant experience, become confusing and overwhelming.
Our sense of smell seems to be intrinsically linked to our memory, and a single whiff can send our minds whirling back to our childhood, our early experiences and the deep-seated emotions linked to them. Incoming smells are processed by the olfactory bulb, which starts in the nose and runs along the bottom of the brain. This has connections to two other areas of the brain; the amygdala and the hippocampus. Both of these are thought to have a strong effect on the generation and recall of memory and emotions. Sight, sound and touch do not pass through these processing centres, which could explain why scent can be such a powerful emotional trigger for us.