This week’s plant profile focuses on the popular poinsettia – I’m sure we all have one at home! I hope you enjoy the read. 🙂
Common name: Poinsettia
Translation: The Latin euphorbia was named after Euphorbus, physician to King Juba II of Mauretania. Pulcherrima is Latin again, meaning “most beautiful”.
Type of plant: Shrub
Origin: Native to Mexico and Guatemala
The ideal growing conditions for Euphorbia pulcherrima are indoors, in bright but filtered light, away from strong sunlight and draughts. They require a minimum temperature of 13 – 15 °C, feeding them once a month with a low nitrogen and high potassium fertiliser is recommended. Water them sparingly as overwatering can damage plants – as a rule of thumb, only water when the surface of the compost has begun to dry out. The flowering life is extended by humidity, so misting them regularly is important.
Propagation: Propagation is easiest by softwood cuttings in May.
Cultivation: Euphorbia pulcherrima is widely cultivated as a garden ornamental in tropical and subtropical areas and grown commercially as a house-plant, in particular for sale during the festive period. They flower from December to January and have a striking display of bright red bracts.
Pest and disease problems: Euphorbia pulcherrima can suffer from grey mould when over-watered, and may also be attacked by common pests of indoor plants such as scale insects and mealybugs.
1. Euphorbia pulcherrima is one of the top-selling potted flowering plants in the USA and are the basis of a multi-million dollar Christmas industry. They have long been associated with the Christian celebration of Christmas and have been used to decorate altars in Guatemala.
2. The common name “poinsettia” was chosen by historian and gardener William H. Prescott in the mid 19th century to honour Joel Roberts Poinsett who introduced the species to the USA in 1828.
3. The genus Euphorbia was named in honour of Euphorbus, the Greek physician to King Juba II of Mauretania (a learned scholar of natural history) in the 1st century AD, who used the latex of Euphorbia species for medicinal purposes. Although many other species of Euphorbia are poisonous, Euphorbia pulcherrima contains only low levels of chemical irritants.
4. There is a story known as “the legend of the poinsettia” which is a Mexican legend that tells of a young girl who couldn’t afford a gift to leave at the manger scene of the local church one Christmas eve. As she watched others give expensive presents, she was very sad and desperately wished she had something to leave for the baby Jesus. Then an angel appeared to the girl and told her that even the most humble gift when given with love would be acceptable. The angel told the child to gather weeds and take them back to the manager. When the girl returned to the church, she lovingly placed the weeds by the manager and suddenly red blossoms sprouted and the weeds became beautiful poinsettias. It was a Christmas miracle.
5. Each tiny, petal-less female flower of Euphorbia pulcherrima is surrounded by male flowers in a cup-shaped series of bracts (modified leaves) known as a cyathium. Each cyathium bears a two-lipped, yellow gland. The green and yellow cyathia are in turn surrounded by a series of large, bright red bracts.
6. Euphorbia pulcherrima latex has been used as a hair removal cream in Mexico and Guatemala, a red dye has even been obtained from the bracts. In Guatemala, the latex has been used as a remedy for toothache and to cause vomiting. Poultices of leaves have been applied to treat aches and pains.
7. Many plants in the Euphorbiaceae family ooze a milky sap. Some people with latex allergies have had a skin reaction (most likely to the sap) after touching the leaves. For pets, the Euphorbia pulcherrima sap may cause mild irritation or nausea. It is best to keep pets away from them, especially puppies and kittens.
8. Euphorbia pulcherrima are often disappointing in their second year, but there are a few ways to try and get a good display from them in their second year. Pruning them back hard in April to about four inches and re-potting and then growing them in a light, cool place over summer – a temperature of 15-18°C – is ideal.
9. The colours of the bracts on Euphorbia pulcherrima are created through “photoperiodism”, meaning that they require darkness (twelve hours at a time for at least five days in a row) to change colour. On the other hand, once they finish that process, the plants require abundant light during the day for the brightest colour.
10. The 12th of December is Poinsettia Day, which marks the death of Joel Roberts Poinsett in 1851. Today Euphorbia pulcherrima is known in Mexico and Guatemala as “La Flor de la Nochebuena” meaning “Flower of the Holy Night” (Christmas Eve).
Plant Names Simplified (Johnson & Smith)
RHS A-Z Encyclopedia of Garden Plants
Kew’s A-Z guide of Plants and Fungi