Aroma Corner
essential oils at home, with care
What essential oils smell like: scent families and 15 popular oils
Most of us are better at smelling than at describing what we smell. Ask ten people about lavender and you will hear "clean", "soapy" and "like my grandmother's drawer". A shared vocabulary helps you shop, guess which oils will sit well together and notice when a bottle has gone off. For botanical names and cautions oil by oil, see the essential oil dictionary.
The scent families
Perfumers and aromatherapists sort oils into families. Books disagree at the edges, but these are the groups used across this part of the site, including the guide to which oils blend well together.
| Family | What it smells like | Examples | Usual note |
|---|---|---|---|
| Citrus | Bright, juicy, like peel being twisted | Sweet orange, lemon, bergamot, yuzu (a fragrant Japanese citrus) | Top |
| Floral | Soft, sweet, petal-like | Lavender, geranium, rose, roman chamomile | Middle |
| Herbal | Green and leafy, a kitchen garden after rain | Rosemary, peppermint, clary sage, marjoram | Top to middle |
| Trees and woods | Dry timber, forest air or sharp, fresh leaves | Cedarwood, cypress, hinoki (Japanese cypress), eucalyptus, tea tree | Leaf oils top, woods base |
| Spice | Warm and peppery, the kitchen cupboard | Black pepper, ginger, cardamom | Middle |
| Resin | Warm, balsamic, incense-like | Frankincense, myrrh, benzoin | Middle to base |
| Exotic and earthy | Heavy, sweet or soil-like, long-lasting | Ylang ylang, sandalwood, patchouli, vetiver | Base |
Top, middle and base notes
An essential oil is a mixture of small molecules that evaporate at different speeds. Top notes, such as most citrus oils, peppermint and eucalyptus, reach your nose first and leave first. Middle notes, such as lavender, geranium and most spices, form the body of a scent. Base notes, such as sandalwood, vetiver, cedarwood and the resins, are slow and deep; on a paper strip they can last until the next morning. The labels are rough, but a blend with something from each level smells fuller and lasts longer than three top notes together.
Fifteen popular oils in plain words
Each entry gives the smell, some good partners and when people tend to reach for it. Read that last part as habit, not prescription.
Lavender (Lavandula angustifolia)
Fresh and floral with a green, herby edge and a soft finish like dry hay. It gets on with almost everything, especially citrus, cedarwood and clary sage, and it is the classic evening oil. Our look at what lavender research does and doesn't show covers the evidence.
Sweet orange (Citrus sinensis)
Like peeling a ripe orange: sweet, juicy and round, with little bitterness. It fades quickly and pairs with spices, frankincense and lavender. People diffuse it on grey winter afternoons for a room that smells friendly rather than perfumed.
Lemon (Citrus limon)
Sharper and cleaner than orange, like freshly grated zest. It pairs with rosemary, eucalyptus and ginger, and people reach for it in the morning. Cold-pressed lemon can make skin react to sunlight, so skin blends need care.
Bergamot (Citrus bergamia)
Citrus with a floral, slightly peppery side; it is the flavour in Earl Grey tea. It sits well with lavender, geranium, ylang ylang and most woods. Ordinary bergamot is strongly phototoxic, so choose "FCF" (bergaptene-free) for skin.
Peppermint (Mentha x piperita)
Cold, sharp and greener than toothpaste; one drop goes a long way. It pairs with rosemary, lemon and eucalyptus, and people sniff it from a tissue on long drives. Keep it away from the faces of babies and young children.
Eucalyptus (Eucalyptus globulus)
Camphor-like and medicinal: cough sweets and sauna steam. It pairs with peppermint, lemon, tea tree and cedarwood and comes out in winter. Keep it out of young children's rooms, and strong scents like this can set off asthma symptoms.
Tea tree (Melaleuca alternifolia)
Fresh, medicinal and slightly spicy with an earthy undertone. Many people find it clinical on its own and nicer with lavender or lemon; it is the usual choice for cleaning sprays. Oxidised tea tree irritates skin more readily, so keep the cap tight.
Rosemary (Salvia rosmarinus)
Green, herby and camphor-like, like brushing past a rosemary bush in the sun (formerly Rosmarinus officinalis). It pairs with lemon, cedarwood and peppermint, and people use it on study days. Avoid it with epilepsy, in pregnancy and around small children.
Roman chamomile (Chamaemelum nobile)
Sweet, fruity and herby, often compared to apples, and strong enough that one drop is usually plenty. It pairs with lavender, mandarin and clary sage in evening blends. German chamomile (Matricaria chamomilla) is a different, inky-blue oil. Take care with both if daisy-family plants give you allergies.
Geranium (Pelargonium graveolens)
Rosy and green at once, with hints of lemon and mint from the leaves. A little reads as "rose" in a blend at a fraction of the price. It pairs with bergamot, lavender and cedarwood, and often turns up in skin-care blends.
Ylang ylang (Cananga odorata)
Heavy, creamy and sweet, with hints of banana and jasmine. A trace is lovely; too much can bring on a headache. It is sold in grades taken from one long distillation, with "extra" the most delicate. It pairs with bergamot and sandalwood in evening, perfume-style blends. Keep it low on skin.
Frankincense (Boswellia carterii or B. sacra)
A peppery, lemony opening that settles into warm resin, like a lighter church incense. It pairs with sweet orange, lavender, myrrh and black pepper, and people choose it for quiet moments and slow breathing.
Sandalwood (Santalum album)
Soft, creamy, milky wood that lasts for hours. It pairs with rose, ylang ylang and frankincense, and people choose it for a scent that stays close. Wild Indian sandalwood was badly overharvested; much of today's oil comes from plantations, and Australian sandalwood (Santalum spicatum) is a drier alternative.
Atlas cedarwood (Cedrus atlantica)
Warm, dry, gently sweet wood that anchors fresher oils such as rosemary, bergamot and cypress. People add it when a blend feels thin. Watch the label: "cedarwood" can also be a juniper (Juniperus virginiana, the pencil-shaving smell) or Himalayan cedar, and each smells different.
Clary sage (Salvia sclarea)
Musky, sweet and herby, somewhere between warm hay and black tea. It is not the same plant as kitchen sage. It pairs with lavender, bergamot and sandalwood in evening blends. Many aromatherapists suggest leaving it out during pregnancy.
Why the same oil smells different from bottle to bottle
Buy lavender from three suppliers and you may get three different smells. Within limits, that is normal.
- Origin and harvest. Soil, altitude, weather and the year all shift the balance of molecules.
- Species. Cheap "lavender" may be lavandin, and "eucalyptus" covers several species.
- Chemotype. One species can make different chemistry depending on where it grows. Rosemary may lean towards 1,8-cineole (sharp), camphor (medicinal) or verbenone (softer), and labels write this as "ct. cineole" and so on.
- Part of the plant and method. Neroli (bitter orange blossom) and petitgrain (its leaves and twigs) come from the same tree, and distilled lime smells unlike cold-pressed lime. The guide to how oils are extracted explains why.
- Age and oxidation. Citrus and pine oils age fastest and can smell flat or faintly of paint thinner. Oxidised oils irritate skin more readily, so replace a bottle that smells wrong. Keep oils in dark glass, tightly closed and cool; many people refrigerate citrus oils and use them within about a year of opening.
- Adulteration. A price far below other suppliers can mean an oil stretched with carrier oil or synthetic aroma chemicals.
How to smell an oil properly
- Use a smelling strip (unscented blotting paper, sold in packs). Write the oil's name in pencil, then dip the other end a few millimetres into the oil.
- Hold the strip a few centimetres below your nose and take two or three short sniffs.
- Do not sniff from the neck of the bottle. The air there is crowded with the lightest molecules, which gives a loud, lopsided version of the oil, and it is easy to get neat oil on your nose.
- Smell three or four oils at most, then rest your nose with some fresh air.
- Come back to each strip after 15 minutes, an hour and the next morning to meet the middle and base notes.
- Note what you smell in your own words. "Like a wet garden" will serve you better than any catalogue description.
A word on mood
Books call oils calming, uplifting or energising, and some small studies have measured short-term changes in mood or alertness after people smell an oil. They are hard to blind (you know what you are smelling), and reviews call the results mixed. Much of the effect comes from preference, memory and expectation: if you dislike lavender, it is unlikely to relax you. Choose by your own nose, and if low mood, anxiety or poor sleep has lasted more than a couple of weeks, talk to a doctor. The US National Center for Complementary and Integrative Health summarises the research on its website.
Smelling safely
Even a strip can bring on a headache, nausea or coughing, and strong scents can trigger asthma. Smell oils with a window open, keep bottles closed and away from children and pets, and keep neat oil off your skin and out of your eyes. And if your sense of smell fades, changes suddenly or you keep noticing smells that are not there, see a doctor. It often follows a cold, but deserves a check.