As a plant, and as an essential oil, dill and fennel can be easily confused. They both belong to the Apiaceae plant family but, although similar in appearance, have slightly (yet some similar) uses as an essential oil in aromatherapy practice. Here’s a closer look at these two plants and how they are both used aromatically.
Dill as a Plant
Dill (Anethum graveolens) is a small annual or biennial herb with the common characteristics of plants of the Apiaceae plant family. It has feathery leaves, umbels of yellow flowers, and produces small flat seeds. Although the leaves of dill are very similar to those of fennel, dill leaves are slightly wider.
Fennel as a Plant
Fennel (Foeniculum vulgare) is a biennial or perennial herb with umbels of golden-yellow flowers, feathery leaves, and grooved seeds. Sweet fennel is the more common variety which is used for aromatic purposes and should not be confused with bitter fennel which usually grows wild.
Dill as an Essential Oil
Dill essential oil is extracted by steam distillation and produces either dill seed or dill weed essential oil, depending on the plant parts that are distilled. Dill seed essential oil has a light, spicy, warm aroma whereas dill weed essential oil is heavier, and sweet and spicy.
Dill seed essential oil is heavily composed of ketones (specifically carvone) and monoterpenes (limonene, phellandrene).1 Dill weed essential oil has similar chemical components but contains less carvone.2 Finally, there are several chemotypes of dill essential oil to consider.
Fennel as an Essential Oil
Sweet fennel essential oil is extracted via steam distillation of the seeds. It has a sweet, anise-like aroma, with hints of earthy pepper.
Sweet fennel essential oil is heavily composed of phenols (such as anethole) and monoterpenes (pinene, limonene, myrcene).1
Use of Dill and Fennel Essential Oils in Aromatherapy Practice
Dill essential oil is used for digestive issues, endocrine, and respiratory issues; these include indigestion, flatulence, amenorrhea, stimulation of milk production in nursing mothers, and as a stimulant in child birth. Due to this last action, it is advisable not to use dill essential oil in pregnancy.
Fennel essential oil is used for digestive issues, skin care, respiratory issues, and endocrine issues; these include indigestion, flatulence, constipation, amenorrhea, edema, mature skin issues, oily skin, rheumatism, bronchitis, asthma, menopausal problems, stimulation of milk production in nursing mothers, and as a stimulant in child birth. Again, fennel essential oil should be avoided in pregnancy. It should also not be used with babies and young children due to its reactive chemical content. Avoid in epilespy, too.
Dill and fennel essential oil have some similar uses in aromatherapy, as members of the same botanical family, but note the difference in chemical components, and use accordingly. In addition, the particular chemotype of dill essential oil used will dictate its primary use.
Learn More About Essential Oils with Sedona Aromatherapie
Consider the Sedona Aromatherapie Linguistics of AromaticsTM program to learn more about essential oils and they are used in aromatic practice!
Caddy, Rosemary, 1997, Essential Oils in Colour, UK: Amberwood Publishing Ltd.
Lawless, Julia, 1995, The Illustrated Encyclopedia of Essential Oils, UK: Thorsons
Author is a 20 year veteran in the health care and aromatherapy industry, a UK-certified aromatherapist, published author in aromatherapy, an approved education provider for the National Association for Holistic Aromatherapy (NAHA), an aromatherapy business owner, a consultant, and Chief Editor for the NAHA Aromatherapy Journal.