The botanical name is Euphorbia pulcherrima; it is also called Poinsettia, since at the time of its first botanical cataloging it was not thought to be an euphorbia, and therefore it was given the name of the first American governor of Mexico. Only later, further studies made it clear that this plant belongs to the large euphorbiaceae family, which includes succulent plants similar to cacti, shrubs, small trees and herbaceous plants. In nature this plant is native to Mexico, although in our day it is also naturalized in many areas of Asia; we are used to seeing small Christmas star plants, but in nature they develop as large shrubs, or small trees, reaching a height of over three meters; in pots it is generally difficult to find poinsettias higher than one meter.
They have thin semi-woody stems, bright green in color, very branched; the foliage is dark, of a particular shape, slightly reminiscent of the holly, despite having thinner and more delicate leaf laminae; at the apex of the stems large inflorescences develop in winter, which we are used to consider as single flowers. In reality the true flowers of the Christmas star are similar to those of all the euphorbias: they are called ciazi and have small dimensions, are practically devoid of petals and are green or yellow.
Those that we consider the large petals of poinsettia are actually bracts, which underlie the inflorescences; this means that they are not petals, but transformed leaves. The botanical species has bright red bracts, smooth and broad; over the decades, however, the success of this plant in cultivation has given way to hybridization; so today we can have poinsettias with pink, fuchsia, yellow, white, striped, variegated, double, curled, rolled bracts. However, it is always the same plant and the same species, and therefore all Christmas stars must be grown in the same way.
Cultivate the Christmas star
In nature these plants live in hilly or mountainous places, characterized by a climate without strong changes in temperature and with fairly high nocturnal lows; do not tolerate temperatures below 12-15 ° C, which can cause the sudden and complete loss of all the foliage. In Italy, therefore, they are cultivated in apartments, or in little heated stairwells.
During the winter they show pretty low night temperatures, so if possible we keep our Christmas star in a room of the house not overly heated and strictly away from heat sources direct, such as radiators or fireplaces; in the same way, we avoid the temperature fluctuations downwards, and therefore we avoid the proximity to doors or windows, to which cold air can enter. Once we find a fairly bright and cool angle, we avoid moving the plant, except by turning it periodically, so that it can enjoy the same brightness from all sides. The soil in which to grow euphorbia will be a good universal soil, lightened with little sand, to avoid water stagnation, which could favor the development of fungal diseases.
Throughout the year we water only when the ground is well dry, this can also mean every day in June or July, and only once a week in winter; avoid leaving the plant completely dry for long, but also keeping the soil soaked in water often; to increase the environmental humidity we keep the vase in a saucer full of expanded clay, always immersed in water, so that evaporation works for us.
If our house is very dry and we like indoor plants, it would be advisable to keep the plants nearby and next to a cold humidifier, which constantly introduces water into the air. The poinsettia leaves are not afraid of being watered by watering, but if we live in an area with very calcareous water, we risk staining them, it is therefore appropriate to wet only the soil. Throughout the year we administer a fertilizer every fortnight, suspending the administration during the flowering period.
|Family and gender|
Euphorbiaceae, Euphorbia pulcherrrima
|Type of plant||In nature shrub of almost 3 meters, in pot maximum 1 meter|
|Exposure||Bright place but without direct sunlight|
|Rustic||Delicate, slightly rustic plant|
|Ground||Light and draining universal soil|
|colors||red, yellow, pink, white|
|Irrigation||Avoid water stagnation|
|Flowering||with very short days,> 12 hours of darkness per night|
Keep a beautiful Christmas star from year to year
Typically, at Christmas time, nurseries are full of poinsettias of various colors, usually obtained by cutting from mother plants. We buy one, we bring it home, we try to make it survive at least for the holiday period, and as soon as it collapses or loses its leaves, we let it dry out, after all the following year we will buy another one. It does not necessarily have to happen this way: it is possible to cultivate a poinsettia in pots for many years, obtaining the typical colored bracts every year in winter.
First of all, we try to cultivate our poinsettia in the best way, watering regularly, providing good quality fertilizer and repotting every two or three years, or when the roots begin to come out of the drain holes in the pot. In addition to this we try to find an ideal position for our plant; in summer the Christmas star can be on the terrace, in a partially shady place; at the arrival of autumn it will be moved to a slightly heated room or to the landing of the stairs, possibly in a bright place, but not near windows or in direct sunlight.
At this point, if we want colored bracts to appear, we will have to consider that these plants bloom only when the days are very short; for this purpose, it is necessary to ensure that the plant receives more than 12 hours of darkness every day, also considering artificial light. For this reason, it is necessary to cover the plants at home, with the dark paper, from 4pm to 8am the next day (more or less).
Generally it is sufficient to carry out this operation for about a week to favor the development of the flowers; at this point, we suspend the fertilizations and leave the plant without cover. At this point let us enjoy the great inflorescences; in spring we will cover all the branches, so as to favor a more compact development of the plant. In the areas of Italy with a very cold winter climate, poinsettias could also live in the garden, although generally even a short period of intense cold can ruin the plants very much, or even destroy all the branches; plants ruined by the cold recover themselves in the spring, but it is usually difficult to see poinsettias in a Sicilian garden, also because of this problem.
Propagate the Christmas star
Poinsettias hardly produce seeds, and above all they are hardly fertile, and even if they were hardly they will produce plants identical to the plant that produced them, since they are always hybrids. For this reason, Christmas stars are propagated by cuttings. These plants tend to root quite easily, both by semi-woody cutting and by woody cutting; for this reason it is possible to prepare cuttings also by using branches that are already well developed, giving rise quickly to a new plant already grown.
More often, however, small cuttings are used, so that they can be trimmed to give rise to more compact and dense, cup-shaped plants. Cuttings of poinsettia are prepared in spring, or even in late summer; the tips of the branches without flowers are taken, the leaves in the lower part are detached and those in the upper part are cut in half, and the cutting is prepared for rooting. Even poinsettias, like all euphorbies, contain large amounts of white latex in their fabrics, which prevents the rapid healing of cuts.
For this reason it is fundamental first of all to take the cuttings with a very sharp knife, so as to avoid producing frayed cuts, which would remain open for a long time. In addition to this, it is important to ensure that no latex comes out of the cuttings before placing them in the ground for rooting. This problem is obviated by rooting the cutting in water, or by placing it briefly in warm water (which stops the latex from escaping), then in the rooting hormone, and then in the soil. The cuttings are produced with the apices of the branches, or even with portions of branch, so as to be able to favor the development of new shoots even in the upper part of the new plant.
Most of the plants that are used during the Christmas period are symbols, more or less clear, of the parties we are going to celebrate. Typically many plants are evergreens, to recall the joy of life, even during winter; many plants used at Christmas time have flowers or red berries, this to recall Jesus Christ, to whom is attributed, in classical iconography, a fiery red mantle, and therefore the red color, typical of Christmas.
The firs were also anciently used to celebrate the end-of-year festivities, as they are cosmic trees, as they are connected between man and the divinity, which resides in the highest sky, where the tops of the tallest trees reach. The holly was already used by the ancient Romans, to keep evil away from home; butcher's broom, used as a holly, even in winter solstice festivals.
The mistletoe, sacred plant for the ancient Celtic populations, becomes sacred also in the legends related to Christ. Along with all these plants, poinsettia becomes a Christmas plant only in more recent times, along with the legend of the little shepherds, who could not donate anything to Jesus in church for Christmas night, they brought a branch taken from a plant found on the street, a red poinsettia in fact.
Pests and diseases
The most typical problems of euphorbia pulcherrima are related to environmental humidity and watering. A plant that tends to sag and lose turgidity, usually needs more frequent watering; Asphyxiated soil, always wet, causes dark spots on the foliage, which tends to become floppy. The margins of the wrinkling leaves are often a symptom of low environmental humidity. A thin gray dust between the leaves or at the base of the stems is instead a clear symptom of an attack of botrytis, a dangerous mold, which tends to develop very quickly. Usually, proper cultivation treatments tend to keep a poinsettia always healthy and lush. If our plant loses its leaves, and tends to suffer a lot, let's try to prune it drastically, so as to favor the development of new and healthy leaves.
What not to do with a Christmas star
There Christmas Star It is a plant of tropical origins accustomed to climatic conditions that are very different from those found on our peninsula during the Christmas period. In nature this plant would certainly not withstand our latitudes but even in the apartment there are some tricks to take if we want this plant to not suffer. In fact, some situations can quickly and irreversibly damage the plant, which in a few days could pass from a state of good health to an intense and generalized deterioration.
Among the wrong behaviors that damage the Christmas star most strongly there is surely the putting of this plant in a wrong place. There are 2 factors that can ruin ours Christmas Star and sometimes not even the holiday season in good condition: light and cold. The light must be continuous but above all the hours of darkness must be continuous and must never be interrupted if you do not want to disturb the plant.
This means that we will have to put the Christmas star in a room where at night no one turns on the light even for a few minutes because this interruption of darkness could ruin the plant in the long run. However, an even more harmful factor for the Christmas stars grown in our apartments is undoubtedly the cold, and in particular the sudden drafts of air that can cause serious damage to the plants.
Poinsettia in fact does not tolerate sudden changes in temperature and when we open the windows of the house to do the cleaning or to change the air we will have to be very careful that the plant is not excessively exposed to air currents. Even a brief chill can cause serious damage to the plant, starting from a yellowing and a consequent rapid defoliation.
Watch the video
How to cure the christmas star
The Christmas star loves to live in a cool environment, especially if it is well lit and sunny. The environment must be humid
visit: how to treat the Christmas star
Christmas star images
On January 6th I received a Christmas star as a gift. Transplanted into a larger pot, it has lost all its leaves
visit: Christmas star images