The Christmas Star
We call it the Christmas Star, although in reality it is a shrub of Central American origin, which has been a great success under the Christmas holidays for some decades, because it is a beautiful houseplant that produces its spectacular inflorescences during the winter , it is therefore suitable to decorate the house during the holidays.
It belongs to the genus Euphorbia, and in nature it develops large or medium-sized shrubs, which can reach two meters in height; the varieties selected for cultivation in the apartment are decidedly more contained, and generally over the years they remain below 100-120 cm in height. They have large, velvety dark green leaves, which tend to turn green ever more clearly if the plant is placed in very intense direct light; the stems are fleshy, semi-succulent and secrete a toxic latex, which can cause skin irritation if it comes into contact with the skin of the hands; let's avoid rubbing our eyes while we handle the poinsettia, because latex is poisonous.
How to grow it
These plants love well-lit positions, but not the direct sun, which often makes the foliage irreparably yellow; they are grown in a good rich and soft soil, very well drained, using not excessively capacious containers, as they show a better development in not too big pots.
Watering must be fairly regular throughout the year, avoiding soaking the soil, and waiting for it to dry between one watering and another.
In summer and winter it is advisable to vaporize the foliage periodically, in order to increase the environmental humidity.
These plants are very afraid of drought, which causes a rapid loss of foliage; they also fear root rots, especially in winter, so we avoid leaving the damp or water soaked soil for a long time.
Throughout the year we dissolve in the water of the waterings little fertilizer for flowering plants, every 15-20 days.
Growing requirements and flowering
In nature, Christmas stars in the cold season can withstand temperatures close to 3-4 ° C, but they fear frost; in the apartment they prefer not too high temperatures during the winter, which could lead to the decay of the plant; so let's keep our euphorbia pulcherrima in a not too heated area of the house, for example the ideal could be a quite bright stairwell.
The plants, in the period of the year characterized by a few pre of daily insolation, begin to produce inflorescences consisting of bunches of small green or yellowish flowers, subtended by enormous red bracts; there are many hybrids and cultivars on the market, with curly bracts, or white or rosy, or even striped.
Christmas star - Euphorbia pulcherrima: A brevidiurna plant
While most of the flowering plants in our garden begin to produce buds and flowers when the days lengthen in late winter or spring, these euphorbias begin to produce inflorescences when the days tend to shorten, between the end of summer and autumn, to then bloom in winter.
When we buy an euphorbia pulcherrima in bloom from the nurseryman this feature does not interest us, because our plant has already been treated in the best way to promote flowering; if, on the other hand, we keep an euphorbia pulcherrima over the years we will realize that it will tend not to flower at all or to do so in a scarce way.
To encourage flowering in the desired period we will have to keep the plant for a few weeks in an area of the house where it receives a few hours of sun a day, including the unnatural light, of home lamps.
In the nursery the plants are forced by keeping them in greenhouses with controlled lighting, where they receive only 3-4 hours of light a day; at home you can try to keep the plant in the light for a few hours and then cover it with a dark bag until the next day; with a little patience, in a few weeks you will see the first buds, so you can leave the plant exposed to natural lighting.