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The Christmas Star Tradition

A plant that symbolises the Christmas season, decorating homes and shops and featured prominently by the florists and garden centres in our cities. We are talking about the Poinsettia, better known to everyone in Italy as the Stella di Natale or Christmas Star. We now associate it with Christmas because of its characteristic bright crimson colour, which on its own is able to create a unique Christmas atmosphere. Not everyone knows, however, that Poinsettias come from far away and have a long history. Let’s discover it together… From ancient legends to the present day It was originally linked to Christmas by a Mexican legend, dating from the 16th century. Pepita, a very poor young girl, was sad because she had nothing to take as a gift to Baby Jesus on Christmas Eve. An angel then appeared before her and assured her that Jesus would accept any gift offered with love. So Pepita gathered a bunch of twigs and grasses along the roadside and took it to the village church. During the Christmas mass, Pepita’s bouquet magically began to germinate and blossomed with very bright red and green flowers. This is why, from then on, the Poinsettia was given the symbolic name of “Flores de Noche Buena” (in Spanish Noche Buena means Christmas Eve), thus becoming the plant that best symbolises Christmas. [caption id="attachment_49041" align="aligncenter" width="500"]

Cover of the book “The miracle of the fist Poinsettia”, with the Mexican legend of Pepita.[/caption] Going further back in history to the time of the Aztechs, we find another legend, according to which the plant is said to originate from a drop of blood from the broken heart of a goddess in love. The Aztechs called this plant “Cuetlaxochitl”, meaning “Flower that withers, mortal flower that perishes like all that is pure". The Cuetlaxochitl was grown as a gift from the gods and Montezuma, the last king of the Aztechs, used it to decorate his palaces. The Aztechs also used the milky sap of the Cuetlaxochitl to cure fever and a red pigment used to dye fabrics was extracted from its bracts. In 1804, the plant was brought to Europe for the first time by the naturalist scientist Alexander von Humboldt. It was catalogued in Berlin and given the botanical name Euphorbia pulcherrima: the most beautiful of the euphorbia. Around 1828, the American ambassador to Mexico, Joel Roberts Poinsett, an amateur botanist, took the plant to South Carolina, in the United States. And it was precisely there, in honour of Poinsett, that it began to be called “Poinsettia”. Moreover, since 12 December 1852 – the anniversary of Poinsett’s death – in the United States “Poinsettia Day” is celebrated. It has become a tradition to exchange Poinsettias on this day – a nice custom that is beginning to catch on in Europe too. [caption id="attachment_49046" align="aligncenter" width="600"]

Poinsettia tree in Mexico.[/caption] From South Carolina, the plant spread to various parts of the United States where the climate was sufficiently warm, including California. Fascinated by the beauty of the red plants that grew wild close to his ranch in California, a plant grower called Paul Ecke decided to start cultivating them. He then began selling the cut branches at Christmas, expanding sales to the whole of the United States. It was apparently the Ecke family's marketing that promoted and spread the association between Poinsettias and Christmas all over the world. A little botany… In its wild state, the Poinsettia is a bush that flourishes in the sub-tropical climate of Mexico and grows to as much as 4 metres in height. Its greatest beauty is without a doubt its “blooms” but, contrary to what is generally thought, its flowers, known as cyathia, are not red but yellow and are surrounded by a crown of red bracts. In botany, bracts are modified leaves that accompany flowers or inflorescences. The actual leaves are green but during the winter period they are almost entirely hidden by their red “sister” leaves. [caption id="attachment_49043" align="aligncenter" width="600"]

The cyathium, the Poinsettia flower, surrounded by a crown of red bracts.[/caption] It is a typically photoperiodic or short-day plant; this is why it flowers in the middle of winter when the days are shortest. A good amount of light favours luxuriant growth, but in order to foster blooms, the plant must stay in the dark for a large part of the day. At our latitudes, it needs to be grown in greenhouses, where over 100 varieties are cultivated. In fact, since it is easy to hybridize, it is offered in new versions: besides the conventional red ones, the most popular, the colour of the bracts may also be cream, powder pink, variegated and edged in white, orange or yellow. Their shape may also vary: lanceolate, dentate or even “curly”... Blue poinsettias, produced by artificial colouring, are less long-lasting. [caption id="attachment_49052" align="aligncenter" width="600"]

Greenhouse where Poinsettia plants are grown.[/caption] How to look after Poinsettias It is not always easy to keep Poinsettias healthy in our homes. However, it is not impossible: here are a few simple hints on how to make these plants last even beyond the Christmas period. Poinsettias survive well in brightly lit rooms with temperatures between 15 and 22°C, but they do not like cold temperatures, sudden changes in temperature and draughts. The ideal temperature, to ensure that they have the deep colour that we know, is around 18°C and, if nebulised regularly with water, they will bloom longer. They suffer when exposed to direct sunlight and if too much water is allowed to remain in dishes beneath pots. Moreover, they suffer when watered directly on their leaves. Use of fertilisers is not recommended when they are flowering; after blooming, they should be fertilised once a month. Contrary to what we are used to thinking, Poinsettias do not die just a few weeks after purchase. Plants should not therefore be thrown away when the flowers fade and the plants lose their leaves and bracts, but should be pruned leaving stems no more than 10 centimetres long, repotted and placed outside, in a place that is well-lit but not exposed to direct sunlight. In October and November they must be kept in the dark (or covered with a black bag) for at least 15 hours a day, from the afternoon to the following morning. It is precisely the dark, in fact, that favours the vegetative stage and development of red bracts. by Benedetta Palazzo

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