The original version of this article was written many years ago for the Dominion newspaper. I happily unearthed it yesterday, ‘filed’ in a large bundle of papers. I’m pleased to have found it again, as I thought, & still think that the information is interesting, & esp. so to someone who spends a lot of time sniffing plants!! I remember hearing once that Eskimos have over 300 words for snow – I wish I had as many descriptive words for scents. When Geoff & I ran the plant nursery, each year we would put out a catalogue, & each time we’d struggle to adequately describe the smells of various plants, both good & not so good. I read an American magazine article, (now many, many years ago) which briefly explained the research of an English gardener called Roy Genders. He suggested classifying the fragrance of plants according to the dominant substances in their essential oils. Of course some plants have ‘roots’ in 2 or more groups.

The first group of chemicals are the ‘INDOLOIDS.” Plants bearing this substance have the dubious honour of smelling like rotting fish or meat. I think that many of the Euphorbia family have this offputting fragrance, also Angelica flowers. Both of these plants attract flies as pollinators, & definitely smell a bit off. Arums tend this way too, & of course the Carnivorous plants utilize this device effectively.

The second group, the ‘AMINOIDS’, whiff of ammonia. We used to grow Epazote, Chenopodium ambrosioides & I think that had a pungent smell like ammonia, Sweet Maudlin, Millefolium & Vietnamese Mint, Polygonum odoratum could be other culprits.  Other oddities we have in the garden are Woundwort, Stachys which smells like a revolting mix of diesel & ammonia. What about the Stinking Gladwin, Iris foetidissima, which smells like roast beef, rather than rotting meat. Once I was part of a working bee, & as we weeded we were all feeling hungry, & muttering dire threats about neighbours cooking roasts, when we realized the alluring smell was emanating from the iris plants we were weeding. Alas it is not at all edible, in fact it’s a toxic plant, & strong purgative. We’ve realised a couple of other plants smell like cooked meat too, Salvia confertiflora & Melianthus.

Another plant that smells tasty but doesn’t live up to it’s promise is the Curry Herb, Helichrysum. It has a deliciously warm curry smell, but the leaves don’t taste spicy at all, strangely enough it’s one of those smells that you can taste… is there a word for that?

The ‘HEAVY’ group, no that’s not the waft of black leather, these are richly fragrant scents overlaid with a hint of putrefaction, (the indole again.) At a distance only the sweet overtones are discernable, but the closer you put your nose the more the indole becomes apparent. Plants in this group include the Tuberose, Jonquils, Lily of the Valley, Honeysuckle & some Viburnums.

The ‘AROMATICS’ all have eugenol present, this is one of the essential oils found in Vanilla, Cinnamon, Cloves & Balsam. This is probably my favourite group of scents. Witch Hazel,Heliotrope, Wisteria & Acacias,are touched with vanilla. Carnations, Viburnum burkwoodii, Sweet Peas & Stocks are definitely of the clove family.

The ‘VIOLET” scented group derive their sweet aroma from ionone. I think, (but don’t know where I learnt) that we can only smell violets for a short while, & then we become immune to their charms. Sweet Scented Mignonette, Reseda odorata has a delicious, sweet edible fragrance, it may not look outstanding, but it’s worth dotting a few plants in the garden for the perfume. The dried roots of Orris Iris, which make Orris powder, take a year or so to mature, & it’s sweet violet smell develops over time. Elecampagne roots have a bit of violet scent plus something a bit more pungent.

The ‘ROSE’ members, incudes not only the obvious… Roses, but also includes the Rose Scented Pelargonium, Pelargonium graveolens which positively oozes geraniol, the alcohol responsible for that rich fragrance. What about that delicious wood from Lawsoniana, it’s almost too good to burn.

When geraniol oxidizes it forms citral, the base of the ‘LEMON’ group, which has many members from the herb family, including Lemon Scented Thyme, Lemon Balm, Lemon Grass & Lemon Verbena, yum.

Leading on from the Lemons, is the ‘FRUIT’ group. The delicious passionfruit smell of Brown Boronia, B. megastigma, Philadelphus with it’s orange overtones, I’ve heard Freesias described as smelling of ripe plums, another almost edible smell. We have an Eglantine Rose in the garden, whose leaves smell exactly like apples,& a Little Robin Geranium smells just like grapefruit, then there’s Pineapple Sage & some of the other scented Pelargoniums. They turn up all over the place, we used to have a coconut scented one, & still have Nutmeg & Peppermint, although the names are sometimes a little optimistic, like the Chocolate Scented version.
Related to the Fruit group is the ‘ANIMAL’ group, chemically similar, but with an additional alcohol. Musk is the commonest fragrance associated with this group, try sniffing Musk & Moss Roses or Grape Hyacinths.

Of course there are a few less appealing members too, the Catnips can be quite feline, True Valerian, V. officinalis roots have the same compound as found in human sweat, I’ve also heard it described as smelling of foxes. A passing whiff is OK but a lingering snort can be overwhelming, not to mention soporific! I think Macrocarpa has a hint of billygoat.

Lastly & sweetly we have the ‘HONEY’ group, Honeysuckles, the tender Cherry Pie Heliotrope, & the sturdy Winter Heliotrope, with it’s rather dull but deliciously fragrant flower heads.I guess in the herb department we also have Camphor, new mown hay (Coumarin) Mint & other familiar scents, & there are still a lot of herbs out there, whose fragrances would be a challenge to describe, but at least this gives us some frame of reference. Isn’t the plant world amazing? I love introducing visitors to our plants & watching their faces as a variety of smells assault their olefactory organs, that’s noses to you & me!

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