Essential Oil Growing Conditions
Environmental conditions are often just as influential in an essential oil’s properties and quality as are the species and plant variety. The location grown and the cultivation methods affect essential oil quality. The type of soil, amount of rainfall, sunlight, humidity and the surrounding environment all play a role in the properties of essential oils. Many oils are further affected by time of harvest and by what other types of plants or trees are grown nearby. The phenomenon of environmental conditions affecting oil properties is called chemical polymorphism. Polymorphism is responsible for plants of the same species yielding essential oils of different “chemical races” or chemotypes.
Growing Conditions and Essential Oil Chemotypes
A good example of the importance of essential oil chemotype is rosemary. The chemical composition of rosemary varies greatly according to whether the plant is grown inland or near the coast. There are also three distinct chemotypes of rosemary, each with different chemical constituents and different therapeutic uses.
The oils from Spain or the former Yugoslavia contain a high amount of camphor or borneol and are called borneol type. Rosemary oils from Africa, distinguished by high cineole content, are called cineole type. And oils from the South of France or Corsica especially rich in verbenone are called verbenone type. The borneol type of rosemary is especially suited for supporting the body to stimulate the liver, in kidney elimination and for relaxing muscles. The cineol type is best used for support of the body to handle catarrhal infections. And the verbenone type of rosemary is best suited to support the body’s skin care and regeneration efforts.
Another good example of the difference between different chemotypes is thyme. There are thyme chemotypes with a strong thymol-8 and /or carvacrol content with powerful antiviral and antibacterial properties. There are additional chemotypes with high percentages of terpene alcohols such as linalool, geraniol, or thujanol, which are used frequently in aromatherapy.
The location the plants were grown and the local environmental conditions can create an entirely different different set of therapeutic properties for the same plant. EOBBD testing will confirm the exact chemotype of the oil, so no guess-work is needed on the therapeutic qualities of the oil.
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