Garlic is a very precious bulbous perennial plant, native to the desert areas of Asia and known and used since ancient times.
Species: Allium sativum
Garlic, whose scientific name is Allium sativum L., belongs to the family Alliaceae and is native to Central Asia.
It is a herbaceous, perennial (but is grown as an annual), bulbous plant, and is grown practically all over the world for its aroma.
It is provided with 40 to 60 cordiform, superficial roots that do not deepen beyond the first 30 cm of soil.
The leaves are basal, enveloping the stem and, contrary to what happens in the onion, they do not function as reserve organs. The leaves are formed by wrapping each other for a long distance so that they are often mistaken as a cylindrical stem. The non-enveloping part of the leaf has a linear shape and is up to 3 cm wide, ending with a sharp point and can reach a total length of 80 cm.
The stem is represented by a small disk called a corm of a few millimeters thick, 2-3 cm long and 1-2 cm wide.
When the flowers are formed, they are carried by flower stems from 40 to 80 cm high which lead to an umbrella-shaped inflorescence at the top. The flowers are small carried by short peduncles, are white tending to red-pink and often do not open and still abort in bud.
The seeds are formed very rarely.
The part we use is the bulb (or head or head) enclosed by a dozen of leaves called "sterile tunics" because they only have a protective function.
Each bulb contains from 6 to 14 cloves or cloves close together and covered with membranous scales. The clove, which represents the organ of multiplication, is attached directly to the stem.
Freshly harvested cloves are unable to germinate as they are in a state of dormancy. To germinate they need to go through a series of physiological stages linked to climatic conditions.
There are numerous species: Allium vineale, Allium ursinum, Alliumfragrans, Allium oreaceum. Among these the most cultivated species is
The species Allium sativum L. of which there are numerous cultivars mostly derived from selection with local populations, are divided into garlic atunica white among which we remember: white garlic from Piacenza, Bianco delFucino, Bianco di Napoli, Bianco Calabrese, Bianco polesano and red tunic garlicamong which we remember the Rosso di Sulmona and the Neapolitan Rosa.
The garlics with red tunic compared to those with white tunic have the particularity of having a slightly shorter cultivation cycle of about a month and much larger bulbs but less suitable for conservation therefore more suitable for immediate consumption.
It has a superficial root system so you have to be careful when working on the soil, which must be light and not deep in order not to damage the roots.
When the flower stems start to appear (which is quite rare) these vannotagliati are still in bud as if they are left on the plant they would use the reserves contained in the bulbs.
If garlic is grown in the open field, it generally does not require irrigation as the rains are sufficient to meet its water needs. It should be borne in mind that when the bulbs begin to swell, which generally, in temperate climate regions coincides with the months of May-June, it takes advantage of watering.
As the bulbs begin to ripen, that is to say when the leaves begin to bend and dry up, it is necessary to stop irrigating as a moist soil, in this period, favors the development of rot.
TYPE OF SOIL AND REPOT
The type of soil to be used for planting garlic bulbs must be light, very fertile, able to avoid water stagnation.
Fertilization must be carried out with exclusively mineral fertilizers as organic ones can cause root rot to the plant so it is recommended to make an organic fertilization to the crop preceding the garlic.
Phosphorus and potassium must be administered during the preparation of the soil before sowing while nitrogen (preferably in the form of ammonium sulphate) is administered twice during cultivation (in cover).
The multiplication occurs through the cloves.
Freshly harvested garlic cloves are unable to sprout or emit roots as they are in a dormant state. To interrupt it, it is necessary to keep it at a temperature of 7 ° C and a humid environment and with the bulbils separated from the bulb.
The cloves must be buried at about 3 cm deep with the apex facing upwards at a distance of 25-40 cm between the rows and 10-15 cm on the row. It takes 8-10 ql / hadi bulbils.
The bulbils should be planted from November to March: in November in the mild climate areas, to have it in the spring to be eaten fresh, in March in the cold climate areas for the garlic that can be stored.
Germination takes place at the expense of the reserve substances contained in the bulbils, so the bigger the bulb, the more rapid the germination will be. Another important factor is the temperature: temperatures around 15-20 ° C allow faster germination.
PARASITES AND DISEASES
There Downy mildew spp. is a fungus that occurs on the aerial parts of the plant. Symptoms present with elongated longitudinal notches of various sizes of white-greyish color. If the humidity is high, they become covered with a gray-violet mold which is nothing more than the spreading elements of the fungus (shooters). The stubborn leaves rot and the vegetation collapses into the ground.
Remedies: first of all they are preventive, being very careful to avoid water stagnation and excessive humidity. The chemical fight consists in using adequate anti-peronosporic products available in specialized centers (photo damage on onion).
White mold caused by a fungus, Sclerotium spp., affects the plant in the early stages of its development both later and can also affect the bulbs after harvesting. The typical appearance of whitish mold is noted on the bulbs. On the leaves starting from the tip and from the outermost ones, there is a yellowing followed by drying.
Remedies: the fight against this fungus is preventive by using both agronomic practices and suitable chemical products. Agronomic practices concern crop rotation while chemical interventions consist in the disinfestation of the soil with fumigation and the use of healthy cloves.
Rot of the bulbs
The rot of the garlic bulbs is caused by a fungus, theAspergillus spp. that I attacked bulbs in the warehouse and manifests itself, if the environment is dry with the mummification of the bulbs, if the environment is humid, with the rotting of the bulbs.The characteristic symptom is the appearance of a yellow or gray-greenish powder which is nothing else that the elements of diffusion of the fungus (conidia) and of black bodies (sclerotia) which are the conservation organs of the fungus.
L'Aspergillus it has saprophytic tendencies (it feeds on dead organic matter in the process of decomposition) and the attack generally occurs following the presence of lesions in the plant or the attack of other pathogens.
Remedies: the fight against these fungi is preventive, that is, being careful to avoid wounds and injuries; excellent cultivation practices that maintain low environmental humidity; use of tanned material (i.e. treated with specific products); perfect drying of the bulbs before storage; maintain an adequate temperature and relative humidity in the storage room.
Rust is caused by a fungus, the Puccinia spp., and the symptoms appear first on the leaves where, in spring, some yellowish spots appear which are nothing more than the propagation organs of the fungus (picnidied ecidia).
Remedies: immediately eliminate the infected material. If attacks are predictable, it is good to use early varieties that are less receptive. Starting from the appearance of the first leaf pustules, it is good to intervene with suitable chemical products available in specialized centers.
The damage is caused by an insect, a diptero, the Delia antiqua and occurs in the bulbs as the larvae of the fly (which overwinters in the ground as a pupa that puffles in spring), born from the eggs that are laid by the adults on the bulbs, feed on the tissues. In the space of a year this insect can make three to four generations. Furthermore, once infested, the bulbs are attacked by bacteria that cause the plant to die.
Remedies: the fight is chemical and agronomic. The agronomic struggle is in the postponement of sowing to avoid the first generation which is the most dangerous. The chemical fight consists in the preventive disinfestation of the soil where the presence of the insect is certain. It is also possible to intervene on adults in the disfarteramento phase with suitable chemical products (photo damage on onion).
Other pathologies that may affect are: nematodesstem and bulb (Ditylenchus spp.); fusarium (Fusarium spp.); virosis (Potyvirus).
A substance was isolated from the steam distillate, theallicin(it is a thiosulfonate) which is responsible for the typical smell of garlic. Allicin is created when the cloves are crushed or cut and is formed following the reaction of alliin (cysteine sulfoxide) which interacts with the enzyme alliinasidando various products among which allicin is the largest representative (about 70%).
COLLECTION AND STORAGE
The garlic harvest is carried out when the leaves are almost completely dry by uprooting the plant and leaving it in the ground to dry for about a week. After that the bulbs can be used normally after having cleaned them from the outer coats, leaves and roots. Very often the bulbs come together in bunches by intertwining the leaves to form the characteristic braids.
If the temperature before and after harvesting is too high or too low, the bulbs may appear translucent, yellowed, moist and in severe cases amber in color and greasy to the touch.
The freshly harvested cloves are not able to germinate they are in fact in a state of dormancy and to germinate they need to go through a series of physiological stages linked to climatic conditions. To preserve their state of dormancy, therefore to use it for culinary use (or as we normally say "not to make it bloom") it is necessary to store it at temperatures of 0 ° C in dry and well ventilated environments.
If the environment is dry, they can be kept for 6-7 months.
Temperatures between 15-18 ° C favor germination.
See: «Medicinal plants: garlic».
USE IN THE KITCHEN
The use of garlic in the kitchen is well known. In all countries of the world this extraordinary plant is used to flavor a large part of foods.
This aromatic plant has been known since ancient times and the earliest known mention of garlic was found in Codex Ebers an Egyptian papyrus dated 1550 BC where various medicaments are mentioned to be made to combat insect bites, headaches and pains in general.
Hippocrates (considered the Father of medicine 460 - 377 BC) recommended this plant for its medicinal qualities.
Pliny the Elder in his famous Historia Naturalis (77 AD) locita for its therapeutic properties as well as theHerbarium of Urbino (manuscript by anonymous author of 1500 preserved in the Vatican Apostolic Library).
The doctors in the Middle Ages they used protective masks stuffed with Garlic to protect themselves against ailments and Russian soldiers, during World War II, carried cloves of garlic in their saddlebags that they had to crush on the wounds to prevent them from becoming infected.
In 1858 Pasteur defines the antiseptic properties of this plant and in the early 1900s Albert Schweitzer (Nobel Peace Prize winner in 1952 who dedicated his life to missions in Africa) used it in Africa to fight dysentery.
The aroma has always been known so much that the same Shakespeare inA Midsummer Night's Dream he makes his actors say in the second scene not to eat garlic because "" ... and above all, actors, my souls, mind you don't eat garlic or onion, because we must all breathe a breath that must be sweet and pleasant ... ".
LANGUAGE OF FLOWERS AND PLANTS
See: «Garlic - The language of flowers and plants».