poinsettia hedge (Euphorbia pulcherrima)

Poinsettia’s time is now. During most of the year, a poinsettia is just stems, or stems and green leaves. Only from late fall until the end of the year does it take on its scarlet color.
But if poinsettia (Euphorbia pulcherrima) is December’s classic botanical beauty, it is joined by several notable relatives that also look their best this time of year. These relatives, all members of the Euphorbiaceae or spurge family, include a prickly cousin covered with flowerlike, button-shaped bracts, a deciduous tree with luminescent burgundy foliage and a highly attractive weed.
You can keep your poinsettia as an indoor plant for years as long as you are diligent in its care, which requires a year of commitment. As January begins, if not before, some of the colorful leaflike bracts will begin to fade and then fall off. Within three to 12 weeks, depending on the variety of poinsettia that you have, there will be nothing but leafless stems to look at.
Cut the stems back to a height of 4 to 6 inches. At this point, you will want to water sparingly, if at all, keeping the soil just moist enough so that the stems do not shrivel.
Around May 1, new leaves should begin to appear. Each time you water – and you should do so frequently once the plant has leafed out – fertilize with a water-soluble product (such as Miracle-Gro) at one-quarter strength of the recommended dosage.
Starting in the middle of September, keep your poinsettia in the dark, by putting a black plastic bag over it or by placing it in a closet, from 5 p.m. until 8 a.m. Just like chrysanthemum, which poinsettia has replaced as the No. 1 potted plant in the nation, poinsettia needs long nights, uninterrupted by any light whatsoever, to flower. If you should briefly shine a flashlight in the closet where your poinsettia is spending the night, it may not turn color in December. If you don’t care when your poinsettia turns red, leave it next to a bright window all year long and it will color up in February.
Poinsettias, indigenous to Mexico, can also be utilized as garden ornamentals where, with proper care, they will grow into 10-by-10-foot shrubs. The poinsettia sitting on your dining room table today may be planted in your garden after it produces leaves in the spring.
Poinsettias are highly picky about soil. Without superior soil drainage, they will die of root rot, so make sure your soil is sandy or heavily amended with compost.
Since poinsettias are native to a moist, tropical climate, they will need protection not only from harsh Valley sun, but from cold as well.
The most robust outdoor poinsettias I have encountered in the Valley – one in Sherman Oaks and the other in Granada Hills – were growing against east-facing walls. Their placement allowed them to avoid hot afternoon summer sun. At the same time, the reflected light and heat from the wall behind them provided a measure of insurance against winter cold.
To be safe, cover poinsettias with burlap or some other insulating material to keep them warm on winter nights.
Poinsettia gets its name from Joel R. Poinsett, who, as U.S. ambassador to Mexico 150 years ago, sent samples of the eponymous plants to his native South Carolina. Later, he developed a business growing and propagating poinsettias in greenhouses and then selling them.
There is a myth about poinsettias being poisonous. I cannot find concrete evidence that anyone ever died from consumption of a poinsettia leaf. Leaves, bracts, stems and white sap have been analyzed, and no toxic chemicals have been found in them. Poinsettia sap, however, like that of all euphorbia species, may cause skin irritation for some people.
Two other holiday plants are actually more of a worry. Mistletoe berries, if eaten, can cause acute stomach pain, heart trauma and even death. The ingestion of holly berries also will result in stomach sickness.
Crown of thorns (Euphorbia milii), a poinsettia relative, is an outstanding plant for providing nonstop color in the garden, not only in winter but in every other season as well. An excellent crown of thorns display may be found on the north side of Ventura Boulevard, just west of the 405 Freeway, in the sidewalk planter of the hotel located there.
Although reasonably cold tolerant, crown of thorns should be covered with protective material when freezing temperatures are forecast.
Chinese tallow tree (Sapium sebiferum), an arboreal, deciduous member of the spurge family, is covered with leaves that turn burgundy this time of year. It is a small- to medium-sized tree, not exceeding 40 feet in height. When young, it has a gorgeous conical shape, especially if planted in an open area where it receives light in equal amounts on all four sides. If at all possible, never prune this tree. Pruning tends to compromise its natural symmetry and unique form.
Petty spurge (Euphorbia peplus) is an annual volunteer that sprouts abundantly throughout the Valley during the winter. While most gardeners consider it a weed, others admit to its charms and let it grow. It does an excellent job of covering bare earth in planter beds and serves as a living mulch that fills in nicely around perennials and shrubs. It dies in the spring. Petty spurge sap is being investigated for its curative properties and has proven to be beneficial in treatment of some skin cancers.
Tip of the week
When selecting a poinsettia, make sure the flower – which consists of small yellow buds in the center of the colored bracts – is intact.
This is a sign that the plant is still fresh and will give an extended color show. If the flower is absent, expect the color of the bracts to fade quickly.
When selecting poinsettias, avoid plants in sleeves or crowded together since they lose leaves and quickly deteriorate when deprived of air circulating around them. If you have to travel very far, they should be transported in a roomy shopping bag. Give them six hours a day of good ambient light, but avoid direct sun exposure and, as is the case with most plants living indoors, water only when soil is dry. Putting ice cubes on the soil surface and letting them melt is a convenient way of watering potted poinsettias and other indoor plants.