Basil Facts, Uses, and History
The aromatic plant of India that we use in our kitchen
Basil, also called great basil, belongs to the Lamiaceae family and its scientific name is Ocimum sp. The word "basil" comes from the Greek word "βασιλεύς", meaning "king", due to the herb's royal and intense aroma.
It is a herbaceous, annual plant, known for its aromatic value, its use in traditional medicine, and its cultivation as an ornamental. The varieties with globular crowns, especially the thin-leaved ones, have an ornamental value, while the broad-leaved ones have mainly a culinary value.
Basil essential oil is used in aromatherapy and perfumery, while it can be also used as an insect repellent. It is considered to be a medicinal-therapeutic plant, also, it is the "king" of aromatics in cooking. It is by far the most popular and widely used aromatic in one of the most famous cuisines, the Italian.
Its beautiful shape and its green color make our spaces more beautiful. It is usually found in pots, yards, balconies, and vegetable gardens.
History of the basil
Basil is a plant native to India, the Middle East, and some Pacific islands. It has been around the Mediterranean for thousands of years but became widely known as a herb in the 16th century by spice merchants in Western Europe.
Its name is referred to in Greek and Roman stories as a medicine during the Elizabethan era, while it is also used in the Orthodox Church.
In Greece, it became known by Alexander the Great around 350 BC. In the early 1600s, Englishmen started using it in their food, while they were also using it as an insect repellent. In New York, basil began to be cultivated and get sold at the end of the 18th century.
During the centuries, it has been spread throughout the world, but in recent years the most important productions are in France, Italy, and Egypt, while Greece also achieves significant yields.
Characteristics of basil
Basil is usually an annual plant, so it completes its biological cycle (germinating, growing, blooming, and producing seeds) within one growing season. This period is between the beginning of spring and the appearance of the first low temperatures (mid-autumn). Some species are preserved and can survive even in the winter. As an ornamental, it can also be cultivated as a perennial, with proper care and pruning.
It is a multi-branched plant and depending on the species/variety it can have a final height of 30 to 60 centimeters (rarely 2 meters). It produces new vegetation all summer long. The color of its leaves varies from light green, and greenish to darker shades of green and even purple. The inflorescence is characterized as botryoid, spike-like, or corymboid. Also, the flowers of the inflorescence can be white, pink, or purple. Its flowers are usually removed to promote vegetative growth (growing more leaves and of better quality).
After flowering and pollination, the fruit is formed, which is tetrachain, and produces its highly aromatic seeds, which are used as food or drink in many countries. According to research, basil has many varieties. Those that are more commonly cultivated are distinguished based on the morphology of their leaves.
Basil Varieties that stand out
Which type of basil should I choose?
The Ocimum species numbers 50-150 different species. The distinction of types and varieties is based on the characteristics of the leaves (such as their size and color) and of the inflorescences (their color), as well as on the different compositions of essential oils. Due to its widespread cultivation and economic importance, the species Ocimum basilicum is of considerable interest with some varieties standing out more.
- Sweet basil (“Genovese” basil)
A famous culinary basil species is the broadleaf or sweet basil with the scientific name Ocimum basilicum var. Genovese thriving in warm and sunny locations.
The size of its leaves is the main characteristic that makes the variety stand out, while it is also responsible for its name. The leaves are large, folded, and oval, with a distinctive aroma and sweet taste. Their final length is about 7-8 cm and they should be cut gradually during growth, in order to allow the rest to grow properly. The height of the plant ranges from 35 to 75 cm and its flowers are usually white.
The variety Genovese has been characterized as a PDO product by the European Union. Its intense aroma is the secret to the world-famous Genovese pesto sauce.
- Purple Basil
Purple basil is a recently developed variety. Its scientific name is Ocimum. It is about 30 cm tall. It is a strongly aromatic plant with purple or violet leaves. Its leaves give color and aroma to several foods, while it is also used for horticultural purposes.
The aromatic plants, especially basil, thrive in sunny places in the garden or on balconies. Nevertheless, this particular species can be placed even in not-so-sunny positions and in almost semi-shady ones. Intense sunshine turns the leaves green, while in places with less exposure to the sun's rays, the foliage retains its characteristic purple color.
- Cinnamon basil
Ocimum basilicum "Cinnamon" comes from Mexico. It is about 45 cm tall and stands out thanks to its reddish stem and white-purple flowers.
- Minimum dwarf (Dwarf bush) basil
Its scientific name is Ocimum basilicum minimum and it is rarely known as curly or bush basil. Micro leaf basil, in addition to the size of its leaves, which are smaller than 1 cm, from which it got its name, is also known for the spherical shape that its crown acquires. It is about 30 cm tall and has whitish flowers.
- Compact bush basil, Ball basil
It is also known as microphyllous basil, curled, or nightshade and has the scientific name Ocimum basilicum var. minimum “Greek”. This basil has smaller and denser leaves than the previous species. It is very famous for its spherical shape and it is also very easy to grow, while it can also grow successfully in a pot.
How to Propagate Basil
The plant with particularly aromatic leaves and shoots can come to our balcony or yard through sowing and transplanting of new plants or cuttings. Cross-pollination between varieties of basil is not so common, so it is difficult to lose the purity of a variety.
- With seed:
The basil seed is dark, hard, small, and oval. Its vegetative capacity depends both on its quality and on environmental factors, such as soil moisture, pH, temperature, light, etc.
For the germination process to begin, the seed must absorb moisture. So it is essential to moisten the respective substrate sufficiently after sowing. Excess water should be avoided [as it can create anoxia (lack of oxygen) in the roots] but ensures adequate relative humidity.
The ideal temperature for rapid germination can vary depending on the variety of seed, but most types of basil will germinate when the temperature is between 20 and 30°C. Conversely, temperatures between 0-5°C and 45-48°C inhibit seed germination. Light helps the process, so we prefer the spots of our seedlings to be as sunny as possible.
Basil can be sown from early spring, by placing one seed per pot or in the ground, at a depth of 3-6 cm, maintaining a distance of 40-60 cm between rows and 20-40 cm on the row. Then, cover the seed with soil, press lightly, and water.
The young plants will not take long to emerge. A few days later (about 8-14 days) depending on the temperature, the first leaflets will be observed which will be aromatic from the start. A month later the plants will have reached 10-12 cm in height. In cases where many seeds have germinated together, the seedlings must be thinned to 20 cm to ensure their best growth.
- With stem cuttings:
Basil can be propagated very easily by cuttings (tender parts of shoots). This procedure is less restrictive than the above in terms of the “adequate” season since it can be done even in autumn. It is enough to choose a robust, unaffected part of the stem of the plant (which has not been wooded), which has not yet flowered, and to cut a "branch" of about 10-12 cm. Then we remove 2-3 leaflets from the base of the part which we have cut and place it in water. The ideal conditions for rooting are 20-25°C (ambient temperature) and diffused light. When the first white roots of the plant start to appear, within the next 2 weeks, then we plant basil in the soil.
- Transplanting existing plants:
We can transplant the thinned seedlings or ready-made young plants that we get from nurseries in pots or suitable parts of our garden. We usually put one plant per pot and one per 40-60 cm in our garden or large pots and planters.
We take care of the roots of the plant during transplanting, while we prefer this process to take place in spring (or until early summer), when the temperature is at more ideal levels, to not stress the plants.
Basil Growing and Care
Since the plant comes from tropical and subtropical countries, it needs high temperatures to grow. The ideal temperatures range from 22 to 30°C, while at higher temperatures we must ensure that the soil of the plant retains sufficient moisture.
Basil is sensitive to low temperatures, let alone to frost, and survives with difficulty during the winter. For this reason, if our plant is in a pot, we can move it to places protected from the cold and frost to extend its lifespan.
The plant thrives in average-textured soils, with a pH of 4.5-8.2 (ideally pH 6.4) and good drainage. Fertile soils rich in organic elements are ideal, while it is a plant that always reacts positively to organic fertilization.
Suitable places for the plant are those with good solar exposure. In places, with full daily sunshine, more leaves are produced with higher essential oil yields. Conversely, heavy shading produces fewer and more faded leaves, but some species prefer semi-shaded places.
It is a plant that seeks sufficient moisture. As a result, frequent watering should not be omitted, so that the soil is always kept moist, especially during summer and hot days, even if we have to water it every day. In the summer, during the hot season, we may need to water every other day or even every day. In any case, it is particularly important not to over-irrigate and not to "flood" the plant, especially when it is in a pot without good drainage. In addition, when watering we should avoid drenching the leaves of the plants.
So the plants should either be watered with furrows or watering basins if we are referring to a large basil crop or a drip system for small and large crops. Accordingly, for plants growing in the garden or pots (domestic use), watering can be done with the hose or the watering can.
Suitable positions for Basil to grow
- In a planter-pot
Basil and other aromatics can be easily grown in pots, that are often placed inside or outside the kitchen.
By providing your plants with the right lighting and ventilation conditions, basil will return you rich and fragrant foliage that will make your space more beautiful.
Especially the micro-leaved varieties grow very well in pots. What could be more beautiful than a pot on the windowsill, a group of plant pots of various sizes, or a vertical hanging herb garden in a sunny part of our kitchen?
- In a vegetable garden
Basil is a very good plant for co-cultivation. It can be grown together with various vegetables because it can repel insects that are harmful to our vegetables. We could say that as integral as it is in the creation of a tomato sauce, the same happens when it comes to planting basil next to tomato plants in our vegetable garden. So it can be grown next to peppers, tomatoes, and other vegetables because of its ability to act as a repellent to some insects.
- In a fragrant garden
A beautiful idea for our garden is the creation of an aromatic garden. That is a delimited area where alternations of aromatic-medicinal plants are planted.
To beautify our aromatic garden, we can place a wooden frame around it, as well as signs with the names of the plants. The plants, depending on the species, can be planted at distances of 20-40 cm to cover the surface from the beginning.
- In flower beds, yards, and gardens
Basil's bright green foliage and compact shape can adorn the corners of our garden, balcony, and flower beds. It is always recommended to co-cultivate with other perennial or annual plants and renew it when it completes its biological cycle. It is good to place basil close to the house, in living areas or outdoor corridors, to enjoy its aroma. As we see in the image above, basil plants of two different varieties are planted in rows next to a living area highlighting their decorative value.
Diseases and Enemies of Basil
How to protect our basil from insects and diseases.
In general, basil is not threatened by many enemies and diseases. By strengthening its robustness and by protecting its natural enemies (e.g. ladybugs) we can protect our plants to a large extent in a biological way.
The biggest problem with basil is the fungus Fusarium oxysporum f. sp. Basilicum. This fungus causes the wilting disease. This particular disease causes reduced growth of the plant, wilting, or even drying of the entire plant in severe infestations. It is preferable not to replant with basil in parts of the garden field where the pathogen has been identified. Avoiding contamination can be done by applying some cultivation practices. By watering the soil directly and avoiding wetting the leaves of the plant, ensuring good ventilation, and strengthening the robustness of our plants we can reduce the risk of infections or the appearance of severe symptoms. Thin-leaf basil varieties with dense foliage are more susceptible to fungal attack than broad-leaf basils.
Entomological enemies of basil
Aphids, mealybugs, cotton bollworms (Helicoverpa armigera), and other garden insects can cause some minor damage to our basil.
The mealybug, also known as the white fly, is a very small insect. The larvae feed on the plant tissues of the leaves and rarely on the shoots, weakening the plant. If the infestation is large, the honeydew secretions of the insects attract fungi which can further weaken the plant. Its eggs are found on the lower surface of the leaves.
To control the populations of this particular insect (as well as other insects) in our garden or balcony, we can make a home preparation by dissolving 25 gr. of green soap in 1 liter of water and spraying our plant once a week. In crops, beneficial insects are well controlled, while we can use yellow traps.
Aphids can quickly build dense colonies with infestations starting from the end of spring. They weaken the plant by sucking its juices and smearing it with their honeydew. They are treated in a similar way to mealybugs.
Holes in leaves can be caused by lepidopteran caterpillars feeding on them. Also, slugs and snails feed on basil leaves. It is good to remove these insects when we notice them on the plant.
If we notice spider webs on the stems of the plant, we have to remove them either with an object or our hands (wearing gloves), without injuring the plant. It may not directly cause a problem for our plant, but it indirectly reduces aeration and its decorative value.
References
- Αρωματικά Φυτά και Βότανα, καλλιεργείστε τα δώρα της φύσης στον κήπο σας, Dr. J. McLeod, M. Kirton, S. Bradley, V. Bradley, G. Burnie, J. Fenton-Smith, D.Greig, 2008
- Ο κήπος με τα βότανα, J. McVicar, 2005
- https://www.actahort.org/books/723/723_45.htm
- https://www.taylorfrancis.com/chapters/edit/10.1201/9780203303771-8/production-systems sweet-basil-eli-putievsky-bertalan-galambosi
- https://www.sciencedirect.com/science/article/abs/pii/S0926669010001858
- https://www.mdpi.com/2223-7747/6/3/41/htm
- https://pubs.acs.org/doi/abs/10.1021/jf960791h
- http://repository.library.teimes.gr/xmlui/bitstream/handle/123456789/827/theka_0268th.pdf?sequence=1
- https://zbook.org/read/43eb62_a-review-on-sweet-basil-seeds-ocimum-basilicum.html
- https://ir.lib.uth.gr/xmlui/bitstream/handle/11615/53495/21221.pdf?sequence=1
- https://apothesis.lib.hmu.gr/bitstream/handle/20.500.12688/673/Katsarou_Maria.2013.pdf?sequence=1&isAllowed=y