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by Dylan Warren Davis:

The Hand Reveals

By Dylan Warren-Davis

Valerian & Fennel
   By Dylan Warren-Davis

The chameleon nature of Mercury is demonstrated in the plant world by two contrasting Mercurial herbs: valerian (valeriana officinalis) and fennel (foeniculum vulgare). Of the rulership of fennel Culpeper says: "it is a herb of Mercury, and under Virgo". Of valerian he says: "it is under the influence of Mercury."[1]

For the purposes of this illustration, it is helpful to see valerian as also linked to Gemini. Mercury frequently rules herbs that are tall, slender and have a feathery foliage. The structure of these plants have a definite ethereal character, in stark contrast to more substantial herbs like comfrey or mullein. This makes photographing Mercurial herbs frustratingly difficult since the slightest puff of wind causes them to sway incessantly. Getting a clear image of them is remarkably elusive!

The odour of Mercurial herbs is described as "highly subtle and penetrating, refreshing to the heart and brain."[2] Both these herbs have very distinctive smells. The smell of valerian, so beloved by cats, is not particularly subtle; in fact the Roman physician Dioscorides is recorded as naming the herb phu after its uniquely pungent quality! Despite its odour, which many find repulsive, it is remarkably refreshing to the heart and brain. By contrast, the smell of fennel is much more subtle and pleasing to the nose, perhaps reflecting the joy of Mercury in Virgo. In New Zealand, where the early settlers introduced the herb for its medicinal uses, fennel has now naturalised and takes up a homologous position at the roadside to cow parsley in Britain. It grows so abundantly in the Kiwi sunshine that, sadly, it is declared a noxious weed. I recall driving along one twenty mile section of road where fennel grew in a dense swath on either side of the carriageway. After driving for a while enjoying the herb's feathery beauty, I saw to my horror a team of tractors flail mowing and reducing it to mulch. Amazingly, as the mangled foliage withered in the powerful sunshine, the air was filled with the intense aniseed-like aroma of fennel. Its refreshing fragrance filled the car and permeated our clothes. After driving a few more miles I realised that I had become quite intoxicated on the aroma and was barely paying any attention to the road. Fortunately the number of other cars on the road in rural New Zealand is very small!

Traditionally the action of Mercurial herbs were seen to:

"have principle relation to the tongue or brain, lungs and memory; they dispell winde and comfort the animal spirits, and open obstructions."[3]

In contemporary herbalism these actions of Mercurial herbs are now described slightly differently, though essentially refer to the same actions. The herbs' influence on the brain and nervous system would be described as a sedative and/or relaxant action. Similarly, their influence on the lungs would be described as an expectorant action, which helps strengthen the lungs, relax the bronchi and clear the mucus from them. The influence on the digestive system would be described as a carminative action, which releases wind and spasm from the bowel. Lastly, Mercurial herbs would generally be described as a tonic for strengthening the vital force.

Valerian is known to have been used for its calming effect on the nervous system since Hippocratic times. Today it is still used for treating a wide range of nervous problems including nervous tension, excitability, anxiety states, insomnia, restlessness, irritability, cramps, headaches associated with stress, migraine and mental confusion. With Mercury opposing the influence of Jupiter, the natural ruler of the lungs, it is interesting that valerian is occasionally used for relieving bronchial spasm in the lungs. It has a further application for helping a smoker's cough, as not only does the herb's expectorant action help clear the lungs, but it also calms the nervous system and hence the need to relieve tension by smoking. A relatively modern application for valerian is for treating high blood pressure and palpitations. The herb's relaxing effect on the nervous system slows down heart rate, releases arterial tension and thereby also reduces a high blood pressure caused by nervous tension. Calming the nerves has the effect of allowing time for the nervous system to recharge itself through improved sleep and relaxation, and the herb can thereby be seen to strengthen the vital force. It is interesting in this connection that the name valerian is thought to be derived from the Latin valeo, valere meaning "to be strong, to be vigourous, to have strength, to be able, to be healthy".

In a similar way, fennel is also used to strengthen the vital force. In fact the ancient herbalists believed that fennel gave strength to the constitution and made fat people grow lean (Mercury opposite Jupiter).[4] The Roman gladiators mixed fennel with their food to increase their strength and it was also used in the wreaths to celebrate the victors after the games in the arena. It is still used to treat obesity today.

In contrast to valerian, fennel is predominantly used to help digestive problems. Its carminative action helps relieve wind and spasm in the bowel, and its gentle action is particularly suited for children and those with delicate stomachs. It increases digestive secretion and is used to awaken the appetite for food, particularly during convalescence. Today its actions are well known for helping those suffering from irritable bowel syndrome. Like valerian, fennel also has an expectorant action and has been traditionally used to help asthma and hiccups. The herb also has a long established use for increasing milk production in nursing mothers. Finally, Culpeper comments on the cooking of fish with fennel:

One good old fashion is not yet left off, viz, to boil Fennel with fish; for it consumes the phlegmatic humour, which fish most plentifully afford and annoy the body with, though few that use it know wherefore they do it; I suppose the reason of its benefit this way is, because it is a herb of Mercury, and under Virgo, and therefore bears antipathy to Pisces.[5]

When valerian is connected to Mercury in Gemini, it is interesting to see this herb as predominantly working on the nervous system and circulation. The Air signs are traditionally connected with the sanguine humour or the blood. By contrast, with fennel ruled by Mercury in Virgo its predominant influence on the digestion is explained, since Virgo rules the intestines.

Notes & References:

  1 ] N. Culpeper, Complete Herbal and English Physician Enlarged, 1653.
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  2 ] R. Folkard, Plant Lore, Legends and Lyrics, 1884, Ch 14.
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  3 ] W. Lilly, Christian Astrology, 1647, p.79.
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  4 ] R. Folkard, Plant Lore, Legends and Lyrics, 1884, section on Fennel in "Encyclopedia of Plants".
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  5 ] N. Culpeper, Complete Herbal and English Physician Enlarged, 1653.
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Dylan Warren-Davis has been practising herbal medicine (naturopathy) for 25 years, qualifying as a prize-winning student with the National Institute of Medical Herbalists (UK) in 1982. Since completing his herbal training, Dylan has researched the lost European metaphysical teachings, upon which Western herbal knowledge is based. He has also been engaged in the commercial production of herbal tinctures and has been a consultant on the manufacturing of herbal tinctures to the herbal industry in Britain. In addition to seeing clients, he is currently promoting glyconutrition in both the UK and Australia.

He may be contacted by email at

 In this series:    Valerian & Fennel: Two Contrasting Mercurial Herbs
 In this series:   Garlic: The embodiment of a Martial herb
 In this series:    Dandelion: The embodiment of a Jovial herb
 In this series:    Comfrey: The embodiment of a Saturnine herb
 In this series:    The Myths of Mistletoe

© Dylan Warren-Davis
This article was published in issue 18 (March 1999) of the Traditional Astrologer Magazine of which Dylan was an associate editor

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