How to plant garlic (Allium sativum)

Garlic is a plant that can grow from 30 cm to 120cm in height. It forms a bulb that contains several segments, usually called “garlic cloves”. In this article we will cover how to plant garlic, when to plant, how to harvest it and the prefered growing conditions.

Note: If you are looking for a guide on how to plant decorative allium, just follow the link.

Garlics can be consumed either raw or cooked. It is generally used as a seasoning or condiment in several types of culinary dishes due to their outstanding flavor. Although less used, young leaves, flower stems, flowers, bulbils that appear with flowers and seeds can also be consumed.

Plant profile

Widely used for medicinal purposes, some studies indicate that regular consumption of garlic offers cardiovascular benefits, in addition to having other beneficial medicinal properties. However, the consumption of garlic produces a characteristic odor on the body and bad breath.

Garlic can also be used as a natural pesticide, and it is common to use garlic extracts or macerates to combat some pests in vegetable gardens.

Garlic seed head

Climate

Garlic can be grown in different climatic regions, there are different cultivars suitable for different regions. However, hot and rainy regions are not suitable for planting garlic. It is necessary a cold period at the beginning or half of the growing cycle, with temperatures between 0°C and 15°C, to stimulate the formation of bulbs (the head of garlic).

The ideal is mild temperatures as the plants grow, with a period of low temperatures at the stage when the bulbs should start to form, followed by warmer months for maturation.

Sunlight

In order to succeed in planting garlic it’s important to choose cultivars adapted to your region. Specifically adapted to the photoperiod, that is, to the hours of light from sunrise to sunset.
There are many cultivars adapted to different photoperiods and climatic conditions, so try to find out about the best cultivars for planting in your region.

Soil

Garlic is not very demanding in terms of soil, and can be planted in less fertile soils, with low nitrogen availability. The ideal is a light soil, well drained and rich in organic matter.
The soil pH can be 5.5 to 8.3 (ideal pH 6.2 to 7). Plant on ridges is recommended if you have heavy clay soil.

How often should I water garlic?

Garlic must be watered frequently so that the soil is always kept moist during the initial growth phase of the plant. Decrease the watering frequency when the bulbs are growing. Stop watering about 10 to 20 days before harvesting.

How to plant

Garlic can be grown from seeds, but it is much more common to plant garlic cloves.

In commercial cultivations it is recommended to separate the cloves by size, as planting cloves of the same size tends to produce more uniform plantations. However, in small domestic gardens, this is less important. Cloves that are very thin, damaged or have signs of decay should be discarded.

Planting is usually done in the fall. In colder regions, it can be planted in late summer, early fall or early spring. In regions with mild winter, planting can be done in autumn or winter. Usually the best heads are harvested from plants that were planted during the fall.

Plant each clove in the final location at a depth of 3 to 5 cm. Can be planted at 8 cm or more in regions with severe winters. Cloves can also be planted in trays or seedbed, being transplanted after they sprout.

It is very important to plant the cloves in the correct position, with the thinnest part facing upwards.

Garlic planted and growing in field

The spacing can be 25 to 30 cm between the planting lines, and 10 cm between the plants. In small plantations, without planting lines, the spacing can be 15 to 18 cm between the plants. Spacing larger than these allows plants to generate larger heads, but productivity per area decreases. Garlic can also be grown easily in pots and planters.

For cultivation in warmer regions, the cloves can be stored under refrigeration (0°C to 10°C) for one or two months before planting is carried out (the appropriate refrigeration period varies with the cultivar).

Growing

Remove invasive plants that can compete with garlic for nutrients and resources while growing, at least during the first three months of cultivation.

Do plant rotation and avoid planting in places where garlic or onions has recently been grown, as growing it in the same location greatly increases the risk of disease.

Harvesting garlic

How do I know the garlic is ready to be harvested? When the older leaves turn yellow and start to dry, it’s time to harvest. It is usually harvested 16 to 36 weeks after planting, depending on the cultivar used, the region where the planting is carried out and the time of year.

Harvested garlic heads

Using a fork, lift the entire plant, without detaching the leaves or the roots. Do it preferably on a dry and sunny day.

Healing is the process in which garlic loses excess water and consists of letting the bulbs dry in the sun for a few days. After this period, when the leaves and the outer layer of the bulbs are completely dry, the bulbs can be stored in cool, dry places, in braids, tied on wooden or bamboo poles, or in trays.

It is important for the conservation of garlic heads to keep them in a dry environment with good ventilation. Garlic bulbs can be stored for up to almost a year, depending on the cultivar and the storage conditions. Loose cloves and damaged heads don’t last long.