Garlic cultivation is widespread in our country because it is an aromatic plant widely used in cooking. We have already talked about the nutritional properties of this bulbous vegetable before. Additionally, we have already explored two recipes for natural insecticides made from garlic, which allow us to treat many of our plants’ diseases naturally.
In today’s article, we will focus on the organic cultivation techniques of this vegetable, so you can grow it both in your garden and in a pot.
The Garlic Plant
Garlic, Allium sativum, is a perennial herbaceous plant. It is classified as an Allioideae of the subfamily Amaryllidaceae, which is why it was once classified as part of the Lily family (Liliaceae). Today, it is considered a plant of the order Asparagales.
As mentioned, cultivating garlic means growing a perennial plant. However, its harvest is on an annual cycle.
It is an aromatic plant with basal leaves that grow up to 60 cm in height. Each leaf wraps around the other in a sort of sheath, scaling towards the inside of the stem.
The roots are cordiform (heart-shaped), dense, and affect the superficial layer of the soil, without penetrating deeply.
When left to vegetate, garlic cultivation produces a beautiful floral scape. This scape has a cylindrical shape and can be 30 to 70 cm long. At the top of the scape, there is an inflorescence with a typical umbrella shape. The flowers can be white or pinkish and vary in number depending on the species.
These are the external characteristics of the cultivated garlic plant, with its most prominent parts naturally represented by the cloves or bulbils.
As we know, these are the plant’s propagation organs. They have a convex shape and start directly from the stem.
The cloves are grouped in variable numbers, from 5 to 20, and form the garlic head.
The garlic head and the bulbils are covered by thin metamorphic leaves, called sterile tunics, which serve as protection.
Each head may have a different weight, depending on the variety and cultivation conditions. In general, it ranges from a minimum of 20 g up to 150 g for a fully developed garlic head.
Garlic Varieties to Grow
In garlic cultivation, especially in home gardens, an important step is choosing the variety. It is important to choose local varieties, or those of peasant origin, perhaps purchased at local farmer’s markets. Cultivating this plant from non-European origins doesn’t make much sense. There are local ecotypes of far superior quality compared to the ones found in pre-packaged supermarket bags.
First of all, when we talk about italian variety selection, we need to distinguish between white and red garlic.
Among the white garlic varieties, three Italian types stand out:
As for red garlic, we have:
- The famous Red Garlic from Sulmona
- French Red Garlic
- Red Garlic of Nubia
Garlic cultivation is straightforward and can be easily done in home gardens with some simple precautions.
When to Sow
The best periods for planting garlic are October and November; the harvest takes place in spring, during May and June.
The plant can withstand low temperatures, although it may suffer from prolonged freezing periods. In excessively cold areas, it is advisable to cultivate in spring, with harvesting in summer. However, it’s essential to keep in mind that the shorter cycle will produce smaller bulbils.
How to Sow
Garlic is sown by burying the bulbils. They should be placed with the tip upwards at a depth of about 3-5 cm.
Therefore, it is easy to reproduce garlic starting from the fruit itself, perhaps conserving seeds from the previous cultivation. Or, after purchasing a particular variety found in a local market.
It is advisable to choose (and conserve) and bury the larger and more vigorous cloves. This way, you will have stronger and more resistant plants during the cultivation cycle.
The recommended sowing distances are at least 15 cm between one plant and another. For the rows, it is best to maintain a distance of 20 cm.
How to Take Care of the Garlic Plant
Garlic cultivation prefers loose and well-worked soil. It is essential that the soil ensures adequate drainage of rainwater. This is because the bulb develops during the rainy seasons. Proper soil drainage is crucial, as waterlogging can lead to rot and cryptogamic diseases. With efficient water drainage in the soil, it is unlikely to have problems with diseases.
If you choose to grow it in pots, you can use universal soil mixed 50% with river sand. This will guarantee good drainage.
Garlic Cultivation in the Field
Garlic grown in the field does not need water assistance. The rainwater it receives is more than sufficient to ensure healthy and lush growth. An emergency irrigation may be necessary in the spring, in case of absence of rain. For this reason, there is no need to set up an irrigation system.
As for fertilization, the cultivar has few nutrient requirements. Organic fertilization before sowing should be avoided, as it can lead to serious rot problems. It is advisable to sow after previous summer crops have been cleared (in the spring) with lighter levels of organic matter.
Cultural Practices during Garlic Cultivation
Garlic cultivation needs to be protected from weeds, which hinder its growth. Periodic weeding operations are necessary. These should be carried out with extreme caution since the roots are superficial. To overcome this problem, it may be appropriate to use a layer of natural mulch, which prevents the spread of weeds.
Another operation performed in the final stage of garlic cultivation is stem bending. This is a small cultivation secret to be carried out about a month before the expected harvest. It is an important precaution as it will favor the enlargement of the buried bulb.
Garlic, as mentioned, is harvested in late spring. The harvest is done manually by uprooting the plants entirely, along with their roots.
In the harvesting period, the soil may be excessively dry, making uprooting difficult. In this case, it is advisable to gently dig around the plant. This way, the operation will be more straightforward, and the stem will be less likely to break.
It is good practice to let the freshly harvested plants dry on the ground for about a week. After this period, the heads must be cleaned of residual soil and the outer and damaged tunics. Then, the roots are cut, and you can create braids or “rests” to hang in a cool, dry place for preservation. If done correctly, this method will preserve the garlic for up to 7-8 months.
Biological Defense against Diseases and Pests
As mentioned several times, garlic is a resistant plant to both diseases and pest attacks. Nevertheless, some viral diseases can occur. The most damaging of these is undoubtedly the mosaic virus. Among the cryptogamic diseases, special attention should be paid to downy mildew, gray mold, rust, and alternariosis. However, these diseases are mostly due to excess water stagnation. By addressing these water problems, the occurrence of such diseases in this cultivation is rare and unlikely.
As for pests, particular attention should be given to the presence of the bulb and stem nematode Ditylenchus dipsaci.
Other pest attacks are very difficult and rare. Let’s not forget the insecticidal properties contained in allicin, a natural antibiotic substance that gives the plant its strong odor.
Due to this characteristic, garlic is used as a natural pesticide. Here are the DIY recipes to make infusion and macerate, fundamental natural remedies to repel aphids and other pests in a completely organic way.
- Oregon State University: “Garlic” – This resource discusses how this plant extracts have been found to have antibacterial and antifungal properties. Thiosulfinates, particularly allicin, are thought to play an important role in these properties.
- Cornell University: “Allicin: Chemistry and Biological Properties – PMC” – This resource discusses allicin (diallylthiosulfinate), a defence molecule from garlic (Allium sativum L.) with a broad range of biological activities.
- University of Wisconsin: “Garlic, Allium sativum – Wisconsin Horticulture” – This resource discusses the health benefits of this vegetable. Allicin in the bulbs has antibiotic and antifungal properties.
- University of Rochester: “Garlic – Health Encyclopedia – URMC” – This resource discusses about the alliin. When this is ground, it makes the strong-smelling, potent antibacterial agent allicin. The plant may have antibacterial effects.
- University of Rhode Island: “Development of Green Garlic as a New Vegetable” – This resource discusses that Green Garlic provides a fresh source of dietary thiosulfinates, which confer the therapeutic properties of garlic (heart healthy) and antimicrobial attributes.