THE THEORY & PRACTICE OF ESSENTIAL OIL BLENDING

Estimated Reading Time: 6 minutes

IN ESSENCE…

• The synergistic blending of pure essential oils can be carried out for both aromatic and therapeutic purposes.
• A highly creative endeavour, blending can be guided by both one’s intuition as well as classifications that align essential oils with their aromas and/or individual characteristics.
• Essential oils have been categorized based on their scent family (e.g. floral vs. woody), their evaporation rate (e.g. top note vs. middle note), and on their therapeutic properties (e.g. calming vs. energizing).
• Using a systematic and highly reflective process, the skills and understanding required to create balanced, harmonious, and pleasant blends can be developed and refined over time.

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INTRODUCTION

Blending essential oils is a highly rewarding activity. Even though the sheer number of essential oils and the possibility of combinations can seem overwhelming, with the backing of some theory and a little bit of precision, intuition, and creativity, making your very own essential oil blends is a very achievable task. Whether the goal is to address a specific ailment or formulate an enchanting fragrance, this comprehensive guide outlines both the theory (Part 1) and practice (Part 2) of the basics of essential oil blending.

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PART 1: THE THEORY OF ESSENTIAL OIL BLENDING

Why blend essential oils at all? Essential oils are volatile aromatic essences of plants that are naturally complex in their composition. This complexity not only forms the rich, unique aromas they exude and the properties they display, but it is also the reason behind the interesting results seen when two or more essential oils are mixed together. Simply put, when essential oils interact with one another, they can bring out superseding effects that cannot be reduced to any individual essential oil. In aromatherapy, this phenomenon is known as ‘synergy’.

Synergy implies that essential oils are, broadly speaking, more powerful in combination than when they act alone. Much like how the musical notes of a compelling melody can come together to give rise to a beautifully poignant and visceral experience, the mixing of certain essential oils can release enticing fragrances and therapeutic effects that may be different to the individual characteristics of any one essential oil.

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THE CLASSIFICATION OF ESSENTIAL OILS

Throughout history, aromas and essential oils have been grouped and classified in a myriad of different ways. These groupings help us understand the simple question: “Which essential oils blend well together?”. Mixing together incompatible oils can give rise to a lifeless or otherwise unpleasant scent, and can even diminish its therapeutic performance. Making a perfectly balanced and harmonious blend, on the other hand, can be therapeutically powerful and also an extremely thrilling and rewarding experience.

There are three basic techniques (or models) for classifying essential oils that are perhaps the most popular. Each of these are outlined below.

Classification Based On Scent Family

In perfumery, scents are often described and portrayed using colorful fragrance or aroma wheels. These frameworks, such as the popular one developed by English historian Michael Edwards, attempt to group different scents into overarching ‘families’ based on their unique natures and perceptual sensations. An underlying proposition in this framework is that there are fundamental relationships between certain scent family members, such that some are more compatible than others when put together.

This same assumption can be applied to essential oil aromas. A simple scent family classification is shown below:

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CITRUS

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Description: Fruity, Tangy
Essential Oils: Lemon, Orange, Grapefruit, Tangerine, Mandarin
Blends With: Floral, Minty, Spicy, Woody

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FLORAL

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Description: Feminine, Soft
Essential Oils: Lavender, Neroli, Jasmine, Geranium, Rose
Blends With: Citrus, Spicy, Woody

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HERBACEOUS

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Description: Green, Grassy
Essential Oils: Clary Sage, Fennel, Rosemary, Thyme, Tea Tree
Blends With: Minty, Woody

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CAMPHORACEOUS

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Description: Intense, Medicinal
Essential Oils: Camphor, Eucalyptus, Cajeput, Pennyroyal, Laurel Leaf
Blends With: Citrus, Spicy, Woody, Herbaceous

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MINTY

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Description: Cooling, Earthy
Essential Oils: Spearmint, Wintergreen, Peppermint
Blends With: Citrus, Woody, Herbaceous, Earthy

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WOODY

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Description: Masculine, Musky
Essential Oils: Sandalwood, Pine, Juniper Berry, Cedarwood, Patchouli
Blends With: Floral, Herbaceous, Minty, Spicy, Citrus

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SPICY

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Description: Warm, Crisp
Essential Oils: Basil, Black Pepper, Cinnamon, Ginger, Nutmeg
Blends With: Floral, Woody, Citrus

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RESINOUS

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Description: Fresh, Piney
Essential Oils: Elemi, Frankincense, Myrrh
Blends With: Citrus, Floral

A straightforward way of blending using this model is to pick essential oils within the same scent family. As the chemical identities of these oils are closely related, they should broadly be compatible with one another. Another technique is to pick essential oils from two scent families that are well-known to blend effectively together. These associations are also listed in the table above; so for example, you would expect Peppermint, which is a Minty oil, to blend well with a Citrus oil such as Grapefruit or a Woody oil such as Pine or Cedarwood.

Classification Based On Evaporation Rate

This technique categorizes essential oils using the analogy of a musical scale. In the 19th century, Septimus Piesse was an English perfumer who speculated that there were similarities in the ways in which humans experience both sounds and smells. A major chord, for instance, consists of a root note, a major third interval, and a perfect fifth interval. When these precise pitches come together in harmony, our brain registers a pleasing and balanced sound. Could the scents of essential oils work in the same way?

It was eventually uncovered that Septimus Piesse had some substance to his theory. Today, the perfume and essential oil industry commonly places essential oils into three overarching ‘notes’, each of which portray a distinctive quality and rate of evaporation.

The top note consists of an essential oil that has a low molecular weight, and therefore hits the olfactory receptors first when you inhale an aromatic blend. It also evaporates quite quickly, which causes the blend’s aroma to evolve and make the other notes much more prominent.

The rate of evaporation of the middle note is not as high as the top note, but it is still faster than the base note. This middle note acts as an essential ‘bridge’ between the lighter and heavier oils within a blend, bringing in a sense of harmony, symphony, richness, and balance.

The base note relates to the essential oil that has the highest molecular weight, and as a result it takes much longer to evaporate. It also ‘holds down’ or ‘fixes’ the rest of the elements of the blend, making the fragrance more secure, binding, and longer-lasting.

PERFUME NOTES

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TOP NOTE

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Evaporation Rate: 0.5 – 3 hours
Common Essential Oils: Bay, Citrus Oils, Eucalyptus, Lavender, Mint Oils, Petitgrain, Pine, Rosemary, Sage

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MIDDLE NOTE

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Evaporation Rate: 2 – 4 hours
Common Essential Oils: Black Pepper, Clove Bud, Cinnamon, Fir Needle, Geranium, Marjoram, Myrrh, Palmarosa, Rose Absolute

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BASE NOTE

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Evaporation Rate: Up to several days
Common Essential Oils: Cedarwood, Frankincense, Valerian, Vetiver, Spikenard, Patchouli, Sandalwood

Using the perfume note theory, we can create fragrances or blends that emanate preferred characteristics. For instance, choosing an oil from all three perfume notes (top, middle, and base) can help create a more complex, well-developed blend that enhances and unfurls over time. In contrast, choosing oils within the same perfume note can give rise to a more homogeneous blend that is uniform in its smell and performance.

Classification Based On Therapeutic Properties

Deviating away from their alluring and exotic scents, essential oils are also well-known for their therapeutic abilities. For example, essential oils such as Lavender, Ylang Ylang, and Valerian are believed to have a distinct calming quality that can soothe anxiety and induce sleep or relaxation. On the other hand, oils such as Lemon, Sweet Orange, and Peppermint are thought to be more stimulating, bringing on a more energetic and lively ambience.

For those looking to make a strictly therapeutic blend, it can be helpful to know how essential oils may be grouped according to their beneficial properties. One such framework is shown below:

THERAPEUTIC PROPERTIES

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APHRODISIAC

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Essential Oils: Clary Sage, Lavender, Litsea Cubeba, Mandarin, Nutmeg, Rose, Rosewood, Sandalwood, Vetiver

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ANTI-INFLAMMATORY

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Essential Oils: Clove Bud, Ginger, Helichrysum, Orange, Roman Chamomile, Turmeric

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ANTISEPTIC/ANTIMICROBIAL

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Essential Oils: Cinnamon, Citronella, Eucalyptus, Lemon, Rosemary, Tea Tree

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BALANCING

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Essential Oils: Blue Tansy, Cedarwood, Juniper Berry, Marjoram, Patchouli, Pine, Spruce, Ylang Ylang

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CALMING

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Essential Oils: Bergamot, Frankincense, Geranium, Jasmine, Lavender, Lemon, Neroli, Ylang Ylang, Valerian

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CARMINATIVE

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Essential Oils: Basil, Cardamon, Cinnamon, Fennel, Ginger, Nutmeg

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DETOXIFYING

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Essential Oils: Cypress, Lemon, Fennel, Juniper Berry, Palmarosa, Patchouli, Peppermint

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STIMULATING

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Essential Oils: Eucalyptus, Ginger, Grapefruit, Lemon, Lime, Peppermint, Rosemary, Sweet Orange

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UPLIFTING

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Essential Oils: Bergamot, Frankincense, Lavender, Lime, Roman Chamomile, Rosemary, Ylang Ylang

This kind of grouping makes it easier to see which essential oils may be combined to produce a specific benefit that you are seeking. For example, to create a blend that promotes relaxation and eases stress, you could choose essential oils that are calming or uplifting (such as Bergamot) and avoid those that are known to be particularly stimulating or energizing (such as Ginger or Grapefruit). Similarly, to make a naturally sultry massage blend that helps enhance and arouse sensual desires, incorporating aphrodisiac oils such as Clary Sage or Sandalwood can be especially helpful.

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WHICH MODEL OR TECHNIQUE SHOULD I CHOOSE FOR MY BLEND?

It is often said that essential oil blending is as much an art as it is a science. This is very true. Each model is simply a guiding force, and which one you ultimately use simply depends on your tastes and preferences. If a particular classification makes more sense to you, or it personally appeals to you in some other way, you can opt for it over others. Different models can also be combined creatively together. For instance, you could select a top, middle, and base note that all belong to one scent family or display a single therapeutic effect. When in doubt, the NDA website lists out blending recommendations for each essential oil product, and provides a valuable starting point.

You will often find that different reference guides, charts, and books will have some level of variation when it comes to groupings. This is due to the complexity and subjectivity that is the very nature of essential oils, and it can sometimes be tricky to place them within a single box or category. Thus, some oils may be classified as both a base note or middle note (an example is Black Pepper oil), and others can be found to be both calming and stimulating to the mind (such as Lemon oil).

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PART 2: THE PRACTICE OF ESSENTIAL OIL BLENDING

This easy-to-follow six-step guide will help you apply the theories above to create your very own aromatic or therapeutic essential oil blend.

Step 1: Understand & Be Mindful Of The Importance Of Safety

The creative blending of essential oils is such a pleasurable activity that it can be easy to forget that these natural volatile oils can cause harm if used incorrectly or without proper safety guidelines in place.

Take care to avoid spillages as pure and undiluted essential oils can cause irritation in the event of skin contact, and can also potentially damage or stain certain materials and surfaces such as rubber, carpets, furniture, or clothes. Essential oils can also irritate the linings of the eyes, so try to keep an appropriate distance when mixing and close bottles when not in use.

As safety information on different essential oils can vary, it is critical to make yourself aware of individual precautions before using each oil, by reading the label on the bottle, checking the manufacturer’s website, or by consulting authoritative texts such as Tisserand and Young’s Essential Oil Safety.

Step 2: Purchase Or Gather Your Blending Equipment

The basic equipment you will need for blending include:

• Amber or cobalt-blue glass bottles of a preferred size (2 mL – 60 mL)
• Glass droppers
• Perfume tester strips
• Labeling tape or stickers
• A marker

Remember that pure essential oils should not be stored in plastic bottles, and can impair rubber tops as well. Glass eye droppers are available for essential oils, and it is best to use individual droppers to avoid the intermixing of different oils.

Step 3: Brainstorm A Selection Of Essential Oils

With the help of the theories and guiding frameworks outlined in Part 1, you can now select which essential oils you would like to use in your blend. Keep in mind there is no one way to use or apply the different categorizations, and they can also be integrated together to suit a particular purpose. You can keep a trusted reference chart or essential oil book with you to consult while you are coming up with ideas. For aromatic blending, NDA has a comprehensive article about essential oil groupings here. Each of our essential oil products also lists out its aromatic profile, which can be used to gather information about their perfume note and scent family.

This step is a very creative and cathartic process, so you should not be afraid to explore different possibilities and combinations, while using your imagination to visualize and experience the end result. The number of essential oils can always be narrowed down later on.

Step 4: Orient Yourself To Each Essential Oil

Getting acquainted with the individual scents of essential oils is an important pre-step before actual blending begins.

The olfactory experience of an essential oil can be quite unique and memorable. When the scent of an essential oil is inhaled, its molecules travel quickly to the olfactory receptors within the nasal cavity. Here, the information gets registered and sent to the brain, including to a set of structures collectively known as the limbic system. The limbic system is responsible for the regulation of emotions and memories; this is why smelling can be a powerful memory jogger and sometimes an intensely emotional experience.

The best way to experience the fragrance of an essential oil is to place a few drops on a perfume tester strip. Then, fan the strip in front of you and inhale. If you like, you can jot down a few words that immediately come to mind. For example, you could ask yourself:

• What is my initial reaction towards this aroma? Is it positive, negative, or neutral?
• What are some words I would use to describe it?
• How strong or intense is this aroma?
• How did it make me feel? Uplifted, calm, balanced, energized?
• Does this aroma remind me of anything? A flower, an object, or perhaps even a memory?

Then, take a short break before inhaling your next desired oil. This is to prevent olfactory fatigue, which can sometimes affect our sense of smell after experiencing an aroma for an extended period of time.

Through this process, you can narrow down and pick out which essential oils you feel will create a strong, harmonious, and pleasant fit once blended together. For beginners, a three-oil blend is typically recommended. To get an initial understanding of how your blend might smell like without potentially wasting any oils, place a few drops on separate perfume testing strips and fan them together before inhaling.

Step 5: Create Your Essential Oil Blend

You should now have a fair idea about which essential oils will be going into your blend. The next step involves a little experimentation to discover the ideal ratios needed for each oil in order for it to rounded and well-balanced.

As is the case with essential oil classifications, there is no one way to decide on which ratio should be used. Initially, a 1:1:1 ratio can be attempted; another popular ratio is 3:5:2, which refers to the top note, middle note, and base note, in that order. So for example, if you decide on the latter ratio and would like your blend to consist of 20 total drops of oil, you would mix 6 drops of your top note, 10 drops of your middle note, and finally 4 drops of your base note. Add your oils in drop by drop into a glass bottle, guided not only by your preferred ratio but also your intuition as the aroma of your blend shifts and morphs and takes on a distinctive shape. There can sometimes be the temptation to add in ‘just one more drop’; to avoid this, be sure to take a small break from time to time to prevent fatigue affecting your blend’s composition.

Step 6: Storing And Using Your Essential Oil Blend

Once your perfect blend has been created, it is time to seal and label your glass bottle, place it in a cool, dark place, and let it evolve and mature for 2-5 days. During this time, a dynamic process takes place, where the constituents of each oil will settle and interact with one another and transform into its final aroma. When it is time to revisit your creation, you can repeat the exploratory questions found in Step 4, which will encourage you to reflect on the aroma as well as take note of things you may need to modify or alter in future blending sessions.

The proper storage of your blend is important to ensure it lasts longer and does not degrade due to ultraviolet light or heat. The best way to store pure essential oil blends is in an amber or cobalt-blue dark glass bottle with a tight-fitting lid and kept away from moisture, heat, and sunlight. Some individuals prefer to store their blends inside a refrigerator.

Finally, determine what would be the best way for you to experience or gain the maximum therapeutic benefits of your blend. To benefit from inhalation, you may add 5-8 drops to an electric diffuser. To make your own personalized fragrance, pour a tablespoon (15 mL/0.5 oz) of Jojoba or Sweet Almond Oil into a roller bottle and add 7-10 drops of your blend. This will create a 2% dilution that can be applied to the wrists, neck, or inner elbows. To incorporate into your beauty routine, you can add the blend to a cosmetic base cream or lotion base at the dilution rate specified by the manufacturer. Alternatively, to create a massage blend, add 10-15 drops to 2 tablespoons (30 mL/1 oz) of a preferred carrier oil. To use, warm the mixture in your hands and rub or massage with gentle strokes until fully absorbed.

Interested in learning more about Essential Oil families and categories, along with their benefits? Read our comprehensive guide here.

Want to discover more about the phenomenon of Synergy? Read our article on the magic of Synergy and Synergy Blends here.

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USING ESSENTIAL OILS SAFELY

It is important to enjoy the benefits of essential oils while using them safely and responsibly. This includes never using them undiluted, performing a skin patch test prior to use, being knowledgeable about the sun’s effects after use, and sourcing them from an ethical brand known for quality and purity.

External use only

As with all other New Directions Aromatics products, essential oils are for external use only. Essential oils must never be used near the eyes, inner nose, and ears, or on any other particularly sensitive areas of skin. It is imperative to consult a medical practitioner before using these oils for therapeutic purposes.

Pregnancy and other health conditions

Pregnant and nursing women are especially advised not to use essential oils without the medical advice of a physician.

Those with the following health conditions are especially recommended to consult the advice of a physician: cancer, heart-related ailments, skin disorders or allergies, hormone-related ailments, or epilepsy.

Individuals that are taking prescription drugs, undergoing major surgery, or who are at a greater risk of experiencing strokes, heart attacks, or atherosclerosis are also advised to seek medical consultation prior to use.

Children and safety

These oils should always be stored in an area that is inaccessible to children, especially those under the age of seven.

How to conduct a skin patch test

Prior to using any essential oil, a skin test is recommended. This can be done by diluting 1 drop of the essential oil in 4 drops of a carrier oil and applying a dime-size amount of this blend to a small area of non-sensitive skin.

Essential oil side effects

Potential side effects of essential oils include redness, rash, hives, burning, bleeding disorders, decreased speed of healing, low blood pressure, dizziness, headache, nausea, diarrhea, convulsions, and rapid heartbeat. In the event of an allergic reaction, discontinue use of the products and see a doctor, pharmacist, or allergist immediately for a health assessment and appropriate remedial action. To prevent side effects, consult with a medical professional prior to use.