Flower Colour & Scent: There’s a Link…

My nose tells me that there must be a genetic link between flower colour and flower scent, but it’s not something written about at all in the garden literature.  Maybe I’d find something in the literature pertaining to breeding for the florist industry, but I don’t know where to look.

As a brand new gardener, aged 17, I made a really dodgy rose garden at my Mum’s place.  I did everything wrong, as you do when you’re starting out.  It’s more than just fortunate that all the mistakes don’t really get in the way of your pleasure.  One of the great things about gardening is that it’s as much fun and just as rewarding when you start out as it is, years later, when you start to know what you’re doing.

That aside, one of the mistakes I made in this circle of a dozen roses, was to choose a dozen different roses.  One of the nice consequences of the mistake was that I quickly came to suspect, and later confirmed (though again only via an accumulation of personal experience), that rose scents are very strongly attached to their colour.  By 19 or 20, I reckoned that, under a blind test, I could guess the colour of any rose by its scent alone.

The pink ones are the most ‘rosey’ – that rose scent like that of rose oil, or rose water, that translates to the flavour of Turkish Delight.  The scent of red roses is altogether deeper, in perfect correspondence with the relative darkness of the blooms.  And the perfumes of autumn-toned roses (my favourite in this group of plants, for which I can’t, even at best, conjure more than mild affection) are sweeter than all the rest, totally distinct, and immediately recognisable.

This is not my dodgy rose garden. This is the rather more successful one on Isola Bella, Italy. The red and pink alternation is, however, dodgy, though there’s no faulting the gardeners skill in growing them, tying them in, etc. If you could actually walk this path (it was roped off), you’d likely experience an alternation of perfumes along with the colours…
Yellow Polyanthus.

Leap, then, to polyanthus. None of these carry a scent except the yellow tones. For this reason alone I’ll choose them over all other colours, which feel one-dimensional in comparison. It is surely no coincidence that the yellows are closest to the wild – and scented – primroses (Primula vulgaris), and perhaps to the cowslip (Primula veris), also scented, though I’m not sure whether the latter contributed to the parentage of polyanthus.

The bog-standard miniature pink florist’s Cyclamen.

I recently wrote on my Facebook page about the stunning scent of Cyclamen purpurascens (in large featured image at top of post), which I argued was possibly the most sophisticated of all flower scents.  I bought a bog-standard miniature pink florist’s cyclamen the other day and was stunned at the perfume.  I assume that this is, like the polyanthus, because it’s genetically closer to the scented species Cyclamen persicum from which it is derived, than the other colours such as white and deep red, which have no scent at all.

And thence to petunias. You can sneer at them, but there’s no denying the appeal of their evening scent, while you’re watering.  I confess I severely underestimated them until I read Christopher Lloyd mention their close genetic relationship with the deliciously perfumed, and altogether more refined Nicotiana. This had never occurred to me before, and had the effect of immediately reducing my prejudice. They went up in my estimation due to the family association (I should add that I’m not proud of the obvious snobbery, but neither will I deny it), and I’ve been loving them (with only a few remaining reservations) ever since.  In perhaps no other commonly grown flower is the association of potency of colour and scent better illustrated.  When it comes to petunias, the deeper the colour, the richer the perfume. The deep purples are the best of all, and totally intoxicating – almost dizzying – after sunset.

This story first appeared on Michael’s blog, The Gardenist, highly recommended reading for gardeners who like to ponder. It’s one of our favourite online reads here at TPH.

When it comes to petunias, the deeper the colour, the richer the perfume.