Description:
Perennial growing to 0.45m by 0.3m.
A dandelion is a short plant, usually with a yellow flower head and notched leaves. A dandelion flower head consists of many tiny flowers. The leaves are 5-25 cm long, simple and basal, entire or lobed, forming a rosette above the central taproot. As the leaves grow outward they push down the surrounding vegetation, such as grass in a lawn, killing the vegetation by cutting off the sunlight. A bright yellow flower head (which is open in the daytime but closes at night) is borne singly on a hollow stem (scape) which rises 4-30 cm above the leaves and exudes a milky sap (latex) when broken. A rosette may produce several flowering stems at a time. The flower head is 2-5 cm in diameter and consists entirely of ray florets.

Distribution and habitat:
Lawn; Meadow; Cultivated Beds.
The Dandelion is at home in all parts of the north temperate zone, in pastures, meadows and on waste ground, and is so plentiful that farmers everywhere find it a troublesome weed, for though its flowers are more conspicuous in the earlier months of the summer, it may be found in bloom, and consequently also prolifically dispersing its seeds, almost throughout the year.

Hystory:
The name dandelion is derived from the Old French, dent-de-lion, which is literally "lion's tooth", referring to the sharply-lobed leaves of the plant. The English spelling reflects the French pronunciation at the time this French word was absorbed into English. The first written usage of the word occurs in an herbal dated 1373, but there is a 1363 document in which the word "dandelion" was used as a proper name (Willelmus Dawndelyon).
In German, the dandelion is called Löwenzahn, which is also translated as "lion's tooth." In modern French the plant is called pissenlit, which means "urinate in bed", apparently referring to its diuretic properties. Likewise, "pissabeds" is an English folkname for this plant, and "piscialletto" is one of its folknames in Italian (with "dente di leone", meaning "lion's tooth"). Similarly in Spanish, it is known as the "meacamas", but also commonly "diente de león".
The name of the genus, Taraxacum, is derived from the Greek taraxos (disorder), and akos (remedy), on account of the curative action of the plant. A possible alternative derivation of Taraxacum is suggested in The Treasury of Botany: 'The generic name is possibly derived from the Greek taraxo ("I have excited" or "caused") and achos (pain), in allusion to the medicinal effects of the plant.'

Parts used:
The root, fresh and dried, the young tops

Constituens:
The principal constituents responsible for dandelion's effect on the digestive system and liver are the bitter principles. Previously referred to as taraxacin, these constituents are sesquiterpene lactones of the eudesmanolide and germacranolide type and are unique to dandelion.
Dandelion is also a rich source of vitamins and minerals. The leaves have a very high content of vitamin A as well as moderate amounts of vitamin D, vitamin C, various B vitamins, iron, silicon, magnesium, zinc, and manganese. 
The leaves are a rich source of potassium, which is interesting since the leaves are used for their diuretic action. This may make dandelion the only naturally occurring potassium-sparing diuretic, although its diuretic action is likely different from that of pharmaceuticals. At high doses, the leaves have been shown to possess diuretic effects comparable to the prescription diuretic frusemide (Lasix). Since clinical data in humans is sparse, it is advisable to seek the guidance of a physician trained in herbal medicine before using dandelion leaves for water retention.  The Bitter compounds in the leaves and root help stimulate digestion and are mild laxatives. These bitter principles also increase bile production in the gallbladder and bile flow from the liver. This makes them a particularly useful tonic for persons with sluggish liver function due to alcohol abuse or poor diet. The increase in bile flow will help improve fat (including cholesterol) metabolism in the body.

Edible Uses:
Edible Parts: Flowers; Leaves; Root.
Edible Uses: Coffee; Tea.
Leaves - raw or cooked. When used in salads, they are rather bitter, though less so in the winter. Tender young leaves are considerably less bitter than older leaves. The leaves are often blanched (by excluding light from the growing plant) before use. This will make them less bitter, but they will also contain less vitamins and minerals. A very nutritious food, 100g of the raw leaves contain about 2.7g. protein, 9.2g. carbohydrate, 187mg Calcium, 66mg phosphorus, 3.1mg iron, 76mg sodium, 397mg potassium, 36mg magnesium, 14000iu vitamin A, 0.19mg vitamin B1, 0.26mg vitamin B2, 35mg vitamin C. Root - raw or cooked. Bitter. A turnip-like flavour. Flowers - raw or cooked. A rather bitter flavour, the unopened flower buds can be used in fritters and they can also be preserved in vinegar and used like capers. Both the leaves and the roots are used to flavour herbal beers and soft drinks such as 'Dandelion and Burdock'. The roots of 2 year old plants are harvested in the autumn, dried and roasted to make a very good coffee substitute. It is caffeine-free. A pleasant tea is made from the flowers. They are also used to make wine - all green parts should be removed when making wine to prevent a bitter flavour. The leaves and the roots can also be used to make tea.

Medicinal Uses:
Aperient; Cholagogue; Depurative; Diuretic; Hepatic; Laxative; Stomachic; Tonic; Warts.
The dandelion is a commonly used herbal remedy. It is especially effective and valuable as a diuretic because it contains high levels of potassium salts and therefore can replace the potassium that is lost from the body when diuretics are used. All parts of the plant, but especially the root, are slightly aperient, cholagogue, depurative, strongly diuretic, hepatic, laxative, stomachic and tonic. The root is also experimentally cholagogue, hypoglycaemic and a weak antibiotic against yeast infections. The dried root has a weaker action. The roots can be used fresh or dried and should be harvested in the autumn when 2 years old. The leaves are harvested in the spring when the plant is in flower and can be dried for later use. A tea can be made from the leaves or, more commonly, from the roots. The plant is used internally in the treatment of gall bladder and urinary disorders, gallstones, jaundice, cirrhosis, dyspepsia with constipation, oedema associated with high blood pressure and heart weakness, chronic joint and skin complaints, gout, eczema and acne. The plant has an antibacterial action, inhibiting the growth of Staphylococcus aureus, Pneumococci, Meningococci, Bacillus dysenteriae, B. typhi, C. diphtheriae, Proteus etc. The latex contained in the plant sap can be used to remove corns, warts and verrucae. The latex has a specific action on inflammations of the gall bladder and is also believed to remove stones in the liver. A tea made from the leaves is laxative.

Others Uses:
Compost; Cosmetict; Dye; Fruit ripening; Latex; Miscellany.
The flowers are an ingredient of 'QR' herbal compost activator. This is a dried and powdered mixture of several herbs that can be added to a compost heap in order to speed up bacterial activity and thus shorten the time needed to make the compost. A liquid plant feed can be made from the root and leaves. A low quality latex, which can be used for making rubber, can be obtained from the roots of this plant. A magenta-brown dye is obtained from the root. The plant releases ethylene gas, this stunts the growth of nearby plants and causes premature ripening of fruits. A distilled water made from the ligules (thin appendages at the base of the leaf blades) is used cosmetictally to clear the skin and is particularly effective in fading freckles.

Dosage: 
As a general liver/gallbladder tonic and to stimulate digestion, 3-5 grams of the dried root or 5-10 ml of a tincture made from the root can be used three times per day Some experts recommend the alcohol-based tincture because the bitter principles are more soluble in alcohol.
As a mild diuretic or appetite stimulant, 4-10 grams of dried leaves can be added to 250 ml (1 cup) of boiling water and drunk as a decoction; or 5-10 ml of fresh juice from the leaves or 2-5 ml of tincture made from the leaves can be used three times per day.
The fresh juice is the most effective.
For chronic rheumatism, gout, stiff joints follow an 8-week dandelion cure as follows:
Use the whole plant before it flowers, leaves during flowering and root only during fall.
Infusion: Steep 2 tsp. Plant or root in 1-cup boiling water. Take 1/2 to 1 cup a day, lukewarm or cold.
Decoction: Use 4 oz. Fresh plant with 2 pints of water; boil down gently to 1 pint and strain. Take 3 tbsp. Six times daily.
Cold extract: Use 2 tsp. Plant with 1 cup water; let stand for 8-hours.
Juice: For a springtime tonic, take 1 tsp. Juice pressed from the leaves in milk, one to three times a day. Use an electric vegetable juicer to extract the milk.
Dandelion root tea: Pour 8 oz. (1/4 L) of cold water over 2 heaping tsp. of the root plus aerial parts, bring slowly to a boil, let steep for 10 to 15 minutes, then strain. Drink 2 cups of tea per day; after breakfast or with breakfast, and before going to bed.

Safety:
Dandelion leaf and root should be used with caution by persons with gallstones. If there is an obstruction of the bile ducts, then dandelion should be avoided altogether.
In cases of stomach ulcer or gastritis, dandelion should be used cautiously, as it may cause overproduction of stomach acid. 
Those experiencing fluid or water retention should consult a nutritionally oriented doctor before taking dandelion leaves. People taking the leaves should be sure that their doctors monitor potassium levels.  The milky latex in the stem and leaves of fresh dandelion may cause an allergic rash in some individuals.