Vietnamese cilantro (botanical name Polygonum odoratum) belongs to the family Polygonaceae. This climbing/ creeping herb is native to Southeast Asia. This plant produces pointed leaves and minor pink-hued blooms. It has a potent, hot mint-like flavour and should always be used in reasonable amounts. This herb is present in supplementation and also used in cooking and baking for garnishing.
Vietnamese cilantro is a tender perennial plant and, in places having temperate climatic conditions, this herb is generally grown as an annual plant or indoors during the winter. This herb multiplies rapidly to form colonies. The herb's stalks tumble and start rooting at its tip. This plant belongs to the genus, which also includes the well-known knotweed and smartweed.
This perennial herb grows best in places lying in the tropical as well as sub-tropical zones, where the conditions are warm and humid. When cultivated in favourable conditions, the Vietnamese cilantro plants may grow up to a height of anything between 15 cm and 30 cm. The plants are likely to wither during the winter or when the temperature shoots up.
The upper surface of Vietnamese cilantro leaves has a deep green with chestnut-hued spots. The bottom side of the leaf has a burgundy color. Each leaf is joined to the stem individually. This herb is found growing in the wild in Vietnam, where the plant is also cultivated extensively. In non-tropical climatic conditions, like in Europe, this plant grows excellently even when cultivated outdoors during the summer. The Vietnamese cilantro has a preference for full sunlight and soils that are well-drained. However, it is important to bring the plant indoors and grown as a house plant. The Vietnamese cilantro seldom blossoms when it is grown in places not having tropical climatic conditions. The leaves, however, possess a potent aroma and flavour, ideal for culinary purposes.
The Vietnamese cilantro yields an essential oil called kesom oil. This oil has high demand in the processed food industry where it is used in the form of a natural food essence. In addition, the cosmetic industry also uses kesom oil.
Many consider the Vietnamese cilantro to be a mystifying and exotic herb. It is a small plant belonging to the genus Polygonum and is frequently employed in Vietnamese cuisines as a substitute for peppermint. On the other hand, most of us are very familiar with the common cilantro, which is used in Salsa, and people across the globe also use the Vietnamese cilantro in several different ways.
Basically, there are three plants that are recognized for their typical 'cilantro' flavour. In addition to the Vietnamese cilantro and the common cilantro (Coriandrum sativum), the third plant in this group is Culantro (botanical name Eryngium foetidium). Although the flavour of the Vietnamese cilantro differs largely from that of Coriandrum sativum, it is much easy to grow the former plant.
As said before the Vietnamese cilantro can also be grown as a perennial in hot climatic conditions, but the plant withers when the temperature rises to 32°C or above. Usually, the plant is cultivated in a big container all through its growing season. It is essential to bring the plant indoors prior to the first frost of the season.
Polygonum, the genus name of the plant, has reference to the several segments of the plant's stems that grow roughly from one joint to another. The plant has a rapid growth and may soon outgrow the container in which it is grown. In case the plant becomes larger than the container, it no longer produces its lettuce-like leaves and requires transplanting into a bigger container or dividing and growing in separate containers. Subject to the size of the original container as well as the growing conditions, this may occur many times in a single growing season. The Vietnamese cilantro is an excellent ground cover and basically grows under the canopy of trees. It grows best in the afternoon shade or during the day when it receives sunlight filtered by trees and lots of water.
The leaves of the Vietnamese cilantro, which have a deep green surface with maroon spots and burgundy colored underside very similar to lettuce leaves, are generally used fresh. Tender Vietnamese cilantro leaves have the best flavour. As these leaves mature, they become firm and leather-like, while their flavour is somewhat pungent or acrid.
You may restrain the Vietnamese cilantro's growth by cutting it down to the ground whenever you wish during the plant's growing season. Doing this will help the plant to produce additional fresh and tender leaves. In case you find that the growth of the plant has retarded after you have cut it back, it is possible that the plant requires being divided or repotting.
In addition to its culinary uses, traditionally, Polygonum Odoratum has also been employed for therapeutic purposes. People have been using this herb to treat nausea as well as fever, besides promoting urine output. The Vietnamese cilantro is also employed in the form of a general tonic as well as to promote hair growth. As this herb possesses anti-inflammatory attributes, it is used for treating sores, ulcers and wounds.
The aroma of Vietnamese cilantro is somewhat like that of lemon, mint and coriander-cilantro. People in Southeast Asia as well as in the Latin American countries use this herb for therapeutic as well as a culinary purposes. Many cuisines in Southeast Asia include the Vietnamese cilantro. It is especially used in poultry, du'a cân and duck egg preparations. When used fresh, the herb has excellent aroma and flavour.
Vietnamese cilantro is a vital ingredient in several cuisines of Singapore and Malaysia. People in these countries use this herb for preparing a spicy noodle soup called laksa. This is a very popular food preparation, which has its origin in the Peranakan culture - a merger of the Malay and Chinese elements. It is so popular that the locals call it daun laksa.
Vietnamese cilantro is a very important ingredient in Vietnamese cuisine. People in Vietnam use the fresh leaves of this herb in salads as well as summer rolls. Often, leaves are also used in soups and stews. Locals also consume the leaves along with boiled, fertilized eggs of ducks.
The flavour of Vietnamese cilantro is somewhat similar to that of common cilantro, but milder. When the leaves become mature, their flavour is similar to that of lemon. The Vietnamese cilantro is also used in the form of a seasoning. This herb is a primary ingredient in pho, a special soup prepared by people in Vietnam. Pho is very nutritious, but contains very low calories. Typically, one bowl of pho contains roughly 650 calories. People in Vietnam and neighbouring countries also use this herb in salads, stir fry and also in the form of a garnish.
The Vietnamese cilantro is an excellent indoor plant. The plant requires high levels of moisture and is appropriate for growing in water gardens and bogs. This plant possesses the aptitude to endure some frosting, provided it frosts for a brief duration. Ideally, the plants should be grown in total sunlight. It grows excellently when cultivated in east, west or south-facing parts of the garden. Ensure that you plant Vietnamese cilantro in a sheltered place, where the plants are properly protected from the weather elements.
This plant is not very particular about the soil conditions, provided the drainage system is good. It is best to plant Polygonum odoratum in a soil having a pH that is between somewhat alkaline and somewhat acidic. The herbs require regular watering during the entire growing season. Ensure that the soil remains moist all through. Never allow the soil to lose moisture and be parched, because this will make the plants wilt quickly and even the quality of the tender leaves as well as their flavour will decline.
It is important to note that the Polygonum odoratum plants do not require much maintenance. Similar to majority of the herbs, Vietnamese cilantro is not vulnerable to any diseases or pests. However, occasionally spider mites may prove to be a problem, especially when the weather conditions are hot and humid. Usually, you can wash off spider mites from the plants by directly spraying a water stream.
It is quite easy to propagate Vietnamese cilantro by means of division undertaken during the spring or in fall. If you are cultivating this species in places having cold northern climatic condition, the plant may possibly require some safeguard against frosts.
Chemical analysis of the essential oil obtained from Vietnamese cilantro has revealed that it encloses long-chain aldehydes, such as dodecanal and decanal. In addition, this essential oil also contains decanol, while sesquiterpenes, such as β-caryophyllene and α-humulene comprise roughly 15 percent of this essential oil.
Vietnamese cilantro is mainly cultivated for its leaves, which are edible. However, this herb may also be grown in the form of a border or bedding plant, especially in cottage gardens. As this is a crawling plant, it is useful in the form of a ground cover.
The fresh, tender leaves of Vietnamese cilantro are harvested in the morning when the morning dew has dispersed, but prior to the sun becoming too hot. The leaves that are collected in the morning preserve additional moisture as well as flavour compared to the leaves harvested during the afternoon when the sun becomes very hot.