Which plants have the most evocative scents of summer? At the risk of being called an introverted snob again (Caroline thinks I don’t read what she puts out about me on Twitter) gardening is so much more interesting when you explore the biology behind it.
Flowers produce scent to lure pollinators to their nectar. So I have concluded that moths must have a much poorer sense of smell than butterflies as flowers that are adapted to pollination by crepuscular insects (those that come out at dawn and dusk Caroline) have the strongest scent of all.
Take Brugmansia, the angels trumpet, pretty enough by day but come early evening there is a moment of drama when the new flowers suddenly dilate (you can actually hear them crackle as they expand), flush pink and suffuse the air around them with an intense intoxicating scent of aniseed which lasts all evening. You can stand it outside during the summer then prune hard and keep frost free over winter.
My second piece of evidence is Mandevilla laxa, an exuberant climber which needs to be containerised, but which also produces breathtaking scent of an evening, this time with hints of vanilla. Further research revealed that they are mostly pollinated by sphingids, night flying hawk moths, how exciting is that! These night scented beauties are either white or very pale coloured, obvious really, when you remember that the colour receptor cone cells in compound eyes don’t work in poor light so it’s only worth appealing to the rod cells which receive purely in monochrome.
My final candidate has an even more interesting pollination story. Magnolias are such an ancient genus that they were around before insects evolved the ability to fly so their broad leathery petals are designed to facilitate access by beetles and the sharp citrus scent of Magnolia grandiflora is one of the highlights of summer.
I’m afraid you won’t get such scientific insight in scent production from either of my two sisters.
You will be relieved to hear that you do not have to carry out any scientific research to appreciate my favoured ‘English-Cottage-Garden’ approach to planting.
Honeysuckle (Lonicera) for example, can contribute wafts of sweet perfume through a summer’s day and on into a warm evening. There are early and late varieties and even winter-flowering ones, but do be careful to choose a scented one – varieties such as ‘Dropmore Scarlet’ look spectacular but don’t smell at all!
My desert-island choice would be L. ‘Graham Thomas’ which isn’t as heartmeltingly pretty as the ones with pink as part of its flower colour-mixture, but displays its muddly white-and-primrose blooms for weeks and weeks from mid-June to August with a rich romantic Midsummers-Night-Dream scent. I recorded a short fuzzy video a while ago to show how to get the best out of this plant.
Sweetpeas are undeniably the obvious choice as a scented annual summer-flowerer, but I’d really like to recommend a tall tobacco plant to you – Nicotiana sylvestris. From seed finer than sand, the seedlings quickly grow into stonking great plants with huge pale green leaves and sticky white single flowers. The perfume from these will blow your socks off on a still evening. One word of warning, the seedlings are a siren to every slug and snail within a five-mile radius…
It might seem obvious, but try to find a sheltered spot near a path for your scented treasures, where the aroma will be held, and someone passing will be near enough to enjoy it. Good luck, Caroline, with that aspect of this week’s topic. I have a bush of myrtle (Myrtus communis) in just such a spot and I take great delight in the spicy scent of its little shiny leaves and single white fluffy flowers.
You knew that you could rely on this particular sister for the classy, not brassy, options, didn’t you………
Did you detect that snooty inference? Pretty rich given my sisters have rather unimaginatively missed a trick this week and only gone for perfumed flowers, overlooking the far more subtle pleasures of scented leaves as you trail your hand through them (or indeed unsuccessfully grab at them on the way down in my case – note broken arm in picture).
Once decorum has been restored, I discovered nothing was more gentile…. just before raising one’s aperitif to one’s lips on a summer’s evening…. than to prettily rub your fingers on the leaves of lemon or mint -scented geraniums, or Salvia ‘Blue Note’ or perhaps ‘Hot Lips’ with pigeons coodling (my word) and the setting sun on your skin. The whole experience is wonderfully sensuous.
The curry-scented foliage of helichrysum or the peanut-butter aroma of melianthus leaves have less sex appeal obviously but they do smell unbelievably strong, and useful for people who like to constantly issue instructions like ‘smell this’ and ‘feel that’ (L & E). But to be fair, one of my enduring love affairs was triggered long ago when Laura insisted I did both with the leaves of her lemon verbena Aloysia citriadora – a truly delicious plant.
NB Louise’s Great Plant this Month will surprise you. It’s far from rare but a star performer in so many respects.