For over 2000 years, the “St. John’s wort” has been known as an important medicinal plant. But this is only one of the names of the plant, it is also called “spotted hard hay” (Tüpfel-Hartheu).
Slightly poisonous plant – can cause skin irritation!
Occurrence and distribution: The St. John’s wort grows, for example, on meager meadows, fallow land and on sunny forest edges. It can also be found on forest clearcuts, under bushes and embankments as well as along paths. It prefers fresh to moderately dry soils. St. John’s wort can therefore often be considered a pioneer plant. It is native throughout Europe. In East Asia, North and South America, and Australia, the plant is considered an introduced plant. The plant is considered a pointer plant for leanness.
Plant description
Growth form: It is a perennial, herbaceous plant that reaches a height between 15 up to 60 cm (more rarely up to 100 cm). The upper part of the plant is clearly branched and has several inflorescences. The stem has a two-edged structure and is filled with marrow inside. A spindle-shaped root with many offshoots forms below the ground. It can reach a length of up to 50 cm. Therefore, St. John’s wort usually forms larger groups. It is the only St. John’s wort with a filled (not hollow) stem.
Leaves: The plant has an ovate to elongated leaf shape and reaches a length of up to 2 cm per leaf. The individual leaves sit opposite on the branched stems. The upper side of the leaves is dark green colored and covered with black dots. Here it should be noted the peculiarity of the leaves. The leaves look like they have holes when viewed against the light, this is due to oil deposits (see also section: Special features of the plant). On the underside of the leaves, the leaf veins are clearly light green in color and protrude from the leaves. The edge of the leaves is smooth.
Flowers: The flower clusters are located at the ends of the branched stems. The individual inflorescences consist of a cyme (this is not a true inflorescence!). – see also section: Special features of the plant). The single flowers consists of five yellow petals, which are rounded at the end and are arranged in a radial pattern around the center of the flower. In the center of the open flower sit the clearly protruding stamens as well as the also yellow colored stigma. It is a hermaphrodite flower. The green colored pointed calyx leaves are formed under the yellow petals. The upper flower parts sit on a green colored ovary. The flower buds have a yellow-black streaks on the outside. The flowering period is from July to August.
Fruits: After flowering, a narrow to egg-shaped three-part seed capsule forms. The individual seeds are only up to 1 mm long. The outside of the fruit capsule is covered with fine, slightly protruding stripes.
Special features of the plant
Specifics of the leaves: The “oil accumulations” are recognizable as small, transparent dots on the leaves. However, the essential oil itself is formed in the black glands on the edge of the leaf. The dots in the leaves are caused by the accumulations of oil, as this softens the cell walls, resulting in a translucent appearance.
Specifics of the flower: The inflorescences are characterized by the shape of growth as a double helix. This is a specific shape of growth. On the main stem of the plant no flowers are formed. They grow exclusively on the left and right side of the main stem! Also the last pair of inflorescences does not form a central flower. This makes the form as a “Trugdolde” – german word for this shape of inflorescence – visible through the plant. The flowers themselves do not produce nectar, but only a pierceable tissue. The edges of the petals / corollas are black dotted. Per flower 50 to 60 (more rarely up to 100) stamens are formed in three groups. Pollination is carried out by bees and bumblebees, as well as flies.
Poisonous plant for humans and pets – advice on how to handle the plant.
Advice on how to handle the plant.: As St. John’s wort contains photosensitizing substances, care should be taken when handling the plant and being exposed to sunlight. Especially in the petals, the blood-red colored hypericin is formed. This can be released by crushing. The best way to detect this is by rubbing the flower buds between two fingers, as these contain a large amount of hypericin. Here, however, gloves should be worn strictly, since contact with the oil can have a phototoxic effect! In any case, gloves should always be worn when handling the plant.
Effect of hypericin: The hypericin contained in the plant can be absorbed by the skin and stored in it. Through sunlight, this substance can be stimulated to fluorescence (term for the glow of dyes by UV light!). This leads to an oxidation reaction within the cells, which causes damage! It thus comes to a cell damage and in the worst case an inflammation of the cells. The ingredient is not changed and remains in the cells. Thus, further reactions may occur over a longer period of time.
Hazardousness for animals
Hazardousness for animals: The toxic dose for the plant is about 100g of fresh leaves for sheep or 0.5 – 0.6% of body weight of fresh plant for cattle / calves. Within 1 to 2 days after ingestion of the plant, the animals develop photodermatitis, restlessness and anorexia. Horses are particularly sensitive to the ingestion of the plant! Immediate decontamination / symptomatic therapy must be carried out on the animals.
Potential use as a medicinal plant
Potential use as a medicinal plant: This section is not intended for self-medication! St. John’s wort can be used as a medicinal plant. The ingredients are considered “slightly toxic”, but for humans they are mostly safe. However, care should be taken when handling the plant! Because the red dye also has a slightly phototoxic effect on humans in connection with sunlight and can also cause skin irritation, especially for people who are susceptible to it. The plant is used, among other things, as an anti-depressant in finished preparations. It acts as a mood enhancer and at the same time has a calming effect. The oil promotes wound healing and is used as an analgesic for rheumatism. In folk medicine, some of the plant is used to make a tea for stomach ailments, as well as for diseases of the liver. The oil, which is extracted from the plant, is popularly called “red oil” – Source: Enzyklopädie: Essbare Wildpflanzen – S. 277
Ingredients: Hypericin (red fluorescent pigment) and pseudohypericin, flavonoids with hyperoside, essential oils, tannins, antibiotically active compounds, phenolic carboxylic acids. The toxicity remains to approx. 20% also in the dry fodder.
Side effects of the plant: The application of St. John’s wort leads to a weakening of other drugs. Therefore, before taking St. John’s wort preparations should be consulted with a doctor to exclude undesirable side effects! Pregnant women are clearly advised not to use the plant, as unexpected complications may occur. An overdose of the plant can cause gastrointestinal complaints and headaches. Very high doses may cause dizziness, clouding of consciousness as well as anxiety. A doctor should then be consulted immediately!
Usage advice from previous sources
Useage from earlier sources: In the work “Fruchtbringenden Gesellschaft“(Merian, 1646) is already mentioned the healing properties of the plant. One of the oldest evidence of the plant is provided in the Viennese Dioscorides – found in the reprint of Berendes (1902). Also in the research / translations of Külb (1855) to the writings of Pliny the Elder from the 1st century: Naturalis historia, Book XXVI. In the New Kreüterbuch of Leonhart Fuchs is also a proof of the earlier use. In the book by Wolfgang Schneider: Lexikon zur Arzneimittelgeschichte. from 1974, the earlier sources are almost completely summarized.
Folk names
Folk names: True St. John’s wort is just one of the plant’s many vernacular names. Others include “Tüpfel-Hartheu (spotted hard hay)”. The name suffix “spotted” refers to the black dots on the flowers and leaves. The name “hard hay” originated from the stalks, which are inedible to animals (bad hay). These are hard and therefore not suitable as hay. In Baden-Württemberg / here especially in Swabia, the plant is known by the name “Hansekraut, Sonnenwendkraut”. These names refer to the flowering time around the summer solstice as well as St. John’s Day (June 24). The plant was revered in ancient Germanic cultures. During the Christianization of the Germanic tribes, it was eventually consecrated to “John the Baptist”. Because of its use against wounds and fever, the plant was also called “Wundkraut, Wundbluemle as well as Fieberkraut”. Due to the blood-red sap it contains, St. John’s wort is also called “Träne Muttergottes (Our Lady’s tear)” as well as “Blutkraut (blood herb)”.
Folk names in connection with legends: Since the healing properties of St. John’s wort were known very early, witches and the devil are said to have detested the herb according to a legend. Out of anger about the healing effect, they are said to have poked small holes in the plant. But since this did not harm the plant, it is said to protect against evil spells and the devil when hung on the house! It is partly also called “Hexen- or Teufelskraut” (witch’s or devil’s herb)!
Folk names associated with customs: True St. John’s wort is an important ingredient in the blessed “Kräuterboschen” (collection of herbs in a bouquet). This is blessed in churches on the Feast of the Assumption of Mary (August 15 – public holiday in germany) and, when hung up in the house, is said to provide relief against evil spirits and thunderstorms. Bundles of the plant were also used to make tufts (known as “Wisch” in Swabian). These could be used to sweep the stove. From this the name “Ofewischle” (oven sweep) has developed.
Name origin
Name origin: The German name “Johnanniskraut” and it’s english counterpart „St. John’s wort“ is said to have developed from the flowering period around St. John’s Day and thus the tribute in favor of “St. John the Baptist”. The name suffix “true” was given to the plant because it is one of the first known St. John’s herbs. The botanical genus name “Hypericum” (ὑπέϱικον – “yperikon”) has two probable derivations from ancient Greek.
Theories of name origin: The first of these derivatives is: from ὑπό (hypo) – in english: “under” – and ἐϱείκη (ereike) – in english: “heathland”. This can thus be translated as “growing under the heathland”.
The second derivation is: from ὑπέϱ (hyper) – in english: “above” and εἰκών (eikon) – in english: “image, likeness, conception”. Since supposedly the healing power of the plant is above all imaginations. (Another unconfirmed meaning may have evolved “because of the handsome flowers“).
Endangerment of the plant
Endangerment of the plant: St. John’s wort is classified as not endangered on the German Red List.
Distribution codes: A, AV, M1, M2, F, K