- Poinsettia plant – peculiarities of growing
- Care for poinsettia at home
- Poinsettia propagation
- Poinsettia diseases
- Poinsettia after flowering
- References and links
Poinsettia is a plant of the genus Euphorbia that belongs to family Euphorbiaceae, naturally growing in the tropics of Mexico and Central America. Poinsettia plant is an evergreen shrub, reaching a height of 13 ft in its habitat, outside its natural environment it is a bush of 12-20 inches in height. The leaves are dark-green, elliptic, petiolate, with serrated edges and 4-6 inches in length. The flowers are yellowish, small, collected in the rosette inflorescence that is surrounded by bright red bracts that are mistaken for flower petals. Also, breeders have created poinsettia varieties with pink, white, yellow and even bi-colored bracts.
Poinsettia flower was named after Joel Roberts Poinsett, the first United States Minister to Mexico, who was fond of botany and was fascinated by the beauty of the plant. Poinsettia flowering starts on Christmas, so sometimes it is called the "Star of Bethlehem" or "Christmas star".
Poinsettia plant – peculiarities of growing
Blooming poinsettia is bought at the store and gifted to the loved ones for Christmas. Usually it dies after flowering, but if you make efforts, you can turn your one-time-purchased poinsettia into perennial plant decorating your house every Christmas. Here are a few tips that help make poinsettia your ally:
- as soon as the leaves begin falling off, reduce watering for the ground to be almost dry, and stop feeding, cut the poinsettia stems at a height of 6 inches from the ground level, put in a dark cool place and let it enter a dormant period until May;
- in May, to stimulate the growth, put a flower in a well-lit place, start watering it and add chemical fertilizers. Once the plant begins growing, transplant it into a new ground;
- in early October put a flower in the box excluding the passage of sunlight for a night, or in a cupboard, where it will be at least 14 hours a day. This will stimulate the development of the plant buds;
- as soon as bracts start opening, care for the plants, as usual.
The peculiarity of poinsettia is that its sap is poisonous. Especially it is harmful for eyes. In some cases, the sap can provoke allergies. When it is in the gastrointestinal tract, it can cause vomiting and intestinal upset. To avoid these troubles, put on gloves before poinsettia pruning and transplanting.
Care for poinsettia at home
How to care for poinsettia
Poinsettia likes living on the western or eastern windowsills, but direct sunlight and drafts hurt it. The most comfortable temperature for the plant growth is 64-77 ºF, during flowering the temperature should be 62-57 ºF, while in the dormant period it should be 57-54 ºF. Watering in summer should be abundant while in winter it should be reduced for the ground to be slightly moist. When Christmas poinsettia blooms, spray it with warm sedimented water.
Use complex mineral fertilizers from spring to autumn twice a month. During flowering you should add potash fertilizer, although many plant growers prefer not to fertilize the plant during the flowering period.
Poinsettia is transplanted in April or May, after a dormant period, when young leaves appear. The soil must be slightly acidic, consisting of a leaf, clay and turf, peat soil and sand in the ratio 2: 3: 1: 1. Do not forget about the drainage layer. Pot should not be much more than the previous one. To ease the stress, transplant the poinsettia by a transferring method.
There are no special requirements about poinsettia pruning. Prune it twice: at the beginning of April, when there is a dormant period, at a height of 6 inches above the ground level, and after a transplanting when new shoots begin to grow. Do this to create a beautiful bush and remove weak shoots that can be used as cuttings for vegetative propagation.
How to propagate poinsettia? In natural environment poinsettia is propagated by seeds, but at home it is propagated vegetatively by cuttings that can be prepared in the early summer. The cutting length should be 3-4 inches with at least 3-6 good buds, the cut must be undertaken directly under the node. Cutting’s cut is immersed into warm water for several minutes for poisonous juice to get away from the plant, then the cut should be treated with a root stimulant. The cuttings are planted into containers with wet substrate consisting of sand, dry manure, and humus and kept at 75-82 ºF under a foil in the light place, but without bright sunshine, occasionally airing and spraying. When the cuttings take root, and this happens in about a month, the temperature can be any but not below 61 ºF. In autumn young poinsettias are transplanted into pots with a diameter of 7-8 inches, but they will start flowering only in a year.
Враги: вредители и болезни пуансетии
Sometimes poinsettia can be attacked by such insects as thrips, scale insects, whiteflies, mealybugs and spider mites. Mealybugs form a waxy white substance, while aphids and whitefly make leaves sticky. To get rid off them you can use natural remedies as well as systemic insecticides. Aphids and scale insects can be removed by weekly wiping the poinsettia leaves on both sides with soapy water, then you should shower the plant to rinse the soap. To fight with scale insects plant leaves should be treated with mineral oil. But sometimes this struggle can be in vain and you still have to go to the store and buy insecticides.
Poinsettia can be infected by gray rot, fusarium wilt, and powdery mildew. Grey rot occurs at high humidity and looks like a musty gray deposit on the shoots and stems, the brown spots appear on the leaves, and gray deposit is formed on inflorescences. To fight with gray rot you should use fungicides. Fusarium wilt makes shoots brown, almost black, then they wither and die. Powdery mildew covers the leaves and flowers of the plant with white deposit, under which the plant gradually becomes brown. To treat these fungal diseases fungicides should be applied.
Why poinsettia leaves turn yellow
When the plant is kept in a cool place and at the same time the soil is regularly overwatered, root rot occurs that is followed by leaves’ yellowing. This is just one of the reasons of such problem. Another reason may be the low humidity that results in affecting the plant with spider mites that make the poinsettia leaves turn yellow.
Why poinsettia sheds leaves
Leaves may fall due to the reasons mentioned in the previous section: overwatered soil at low temperature and too dry air in the room. It means that at first leaves turn yellow and then fall off. Yellow leaves also fall due to the lack of watering. When Christmas holidays are over, poinsettia turns yellow and sheds leaves to get prepared for a dormant period. Sometimes leaves falling occurs due to extreme temperatures or lack of lighting.
Why poinsettia does not bloom
Most likely, the reason is that you did not complete all agricultural recommendations of experts. Carefully read again the section on poinsettia bloom, and maybe you find your mistake by yourself. The main condition that the plant needs to bloom is the right light and temperature.
Poinsettia after flowering
Poinsettia dormant period starts in March and April, it lasts about six weeks. When the plant begins to drop leaves, you should cut its shoots at a height of 6 inches from the ground level, put the poinsettia in a dark cool place and let it rest, only moisten the soil in the pot occasionally and very moderately. In May, your beauty will wake up and will require your care and attention, for which it will thank you at the onset of winter with the bright festive flowering.
References and links
- Read also about topic at Wikipedia
- Features and other plants of the family Euphorbiaceae
- List of all species on The Plant List
- More information at World Flora Online