How to maintain Christmas flowers?

Poinsettia, also known as Christmas flower and old pepper, is a color-changing foliage plant native to Central Africa. Its flowers are so small that they are not easily noticed. What is striking is that the leaves at the top of plants will turn dazzling red after winter. The flowering period lasts from1February to February of the following year, and coincides with Christmas, New Year's Day and Spring Festival, which is very suitable for the festive atmosphere of the festival. Poinsettia likes warm, humid and ventilated environment and can't stand low temperature. Too much sunlight and insufficient light are also not conducive to growth. During the growing period, fertilizer and water management and top-level maintenance should be done well. When watering, we should pay attention to prevent it from being too dry and wet, otherwise it will cause the leaves at the lower part of the plant to yellow and fall off, and the branches will grow unevenly. When the weather is hot in summer, we should increase the watering amount appropriately, but don't accumulate water in the basin to avoid causing root rot. Other seasons depend on the dry and wet conditions of the soil in the basin. Poinsettia is not strict with soil, but generally fertile sand is fine. When changing pots, decomposed organic fertilizer should be added as base fertilizer in time, and liquid fertilizer should be applied every half month during the growth and flowering period. After autumn, some fertilizers rich in potassium and phosphorus can be added to promote flower bud differentiation and ensure bright red and pure bracts. Poinsettia grows rapidly after entering the growth period. At this time, we must pay attention to picking the heart and fixing the head, otherwise the branches will grow too high, which will not only affect the appearance and shape, but also reduce the ornamental value. The propagation of poinsettia can be carried out by cutting. In spring and summer, cut a branch and apply some plant ash to the wound to prevent it from rotting. It can take root after being inserted into the soil for about 25 days. In addition, the juice of poinsettia is poisonous, so don't touch it when pinching and cutting, so as not to cause skin discomfort.

Cultivation steps

poinsettia

Poinsettia, Euphorbia deciduous erect shrub. Simple leaves alternate, elliptic to broadly lanceolate, 10 to 15 cm long, hairy on the back, and narrow leaves (also known as bracts) are inserted at the top of branches. Poinsettia is native to Central America and potted in northern China. Flowering period is 65438+February to February of the following year. First, the propagation method of poinsettia generally uses clay pots or sinks for cutting, and shoots and dormant branches can be used. Cutting should be carried out after flowering in early spring, using dormant branches, each cutting 10 cm. Air-dry for 2-3 days aft cutting, or fully air-dry milk stained with soot at that cutting mouth, and plant the milk in plain sandy soil, wherein the depth is one third of the cutting length, and the spacing is about 5cm. After sowing, water it, place it in a ventilated and semi-cool place, keep the temperature at 15-20℃, and keep the pot soil dry and wet. New roots can be born in about a month. When the new shoots grow to 10 cm, they can be planted in small flowerpots. Second, the preparation of cultivated soil Poinsettia likes loose and well-drained soil. Generally, 3 parts of vegetable garden soil, 3 parts of humus soil, 3 parts of humus soil, decomposed cake fertilizer 1 part, and a small amount of slag are used together. Third, the temperature poinsettia likes warmth and is afraid of cold. When entering the room in the middle and late September every year, it is necessary to strengthen ventilation to make plants gradually adapt to the indoor environment, and the room temperature should be kept at 15℃ to 20℃ in winter. At this time, it is in the stage of bract discoloration and flower bud differentiation. If the room temperature is lower than 15℃, flowers and leaves will be stunted. In mid-June, it will be in full bloom after 5438+February, and it should be ventilated gradually. Fourth, the illumination poinsettia likes sufficient light and has strong phototropism. It is a short-day plant. Adequate light should be obtained all the year round, and the discoloration of bracts, flower bud differentiation and flowering period are more important. If the light is insufficient, the branches are easy to grow white, easy to get sick and dim in color. If they are kept in the shade for a long time, they won't bloom and fall leaves in winter. In order to advance or delay flowering, light can be controlled. Generally, the light is 8 to 9 hours a day, and flowering can last for 40 days. Five, fertilization Poinsettia likes fertile sand. In addition to adding organic fertilizer and horseshoe slices as base fertilizer when releasing and changing pots, in the growing and flowering season, apply 5 times diluted and fully decomposed sesame paste liquid fertilizer every 10 ~ 15 days. After autumn, you can also apply/kloc-0 0.3% compound fertilizer once a week for 3 ~ 4 times in a row to promote the discoloration of bracts and flower bud differentiation. 6. Watering poinsettia is not drought-resistant and water-resistant, and watering should be flexibly controlled according to the weather, soil and plant growth. Generally, water should be used to keep the basin soil moist and free of water, but water should be reduced after flowering. Seven. Tomb-Sweeping Day was trimmed before and after, the dormant old plants were changed into pots, the old roots and weak branches were cut off, and new techniques were popularized to germinate. In the process of growing up, you need to pick your heart twice, the first time in late June and the second time in mid-August. Large amount of fertilizer and water should be controlled in cultivation, especially before the plant is finalized in autumn. When the branches grow to 20 to 30 centimeters, they will be shaped and bent. The purpose is to make the plants short, the flower heads neat and evenly distributed, and improve the ornamental value.

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Fertilizer and water management

poinsettia

In order to achieve the best quality of poinsettia, the management of fertilizer and water is also very important. There is a great demand for fertilizer, and the fertilizer components needed in each growth period are also very different, especially in the vegetative growth period. As mentioned earlier, from the time when cuttings take root (about 15 days), fertilizer supply is indispensable from irrigation to flowering and sales. The main nutrient elements needed by poinsettia plants are nitrogen, phosphorus, potassium, calcium, magnesium, manganese, zinc, boron, molybdenum and other elements, and the lack of any one will lead to bad symptoms. Application principle Choose suitable fertilizer according to the growth situation, fertilizer demand and growth cycle of each period, and master the principle of diligent application and thin application. And we should know the role of nitrogen, phosphorus, potassium and other components in each period of the whole cultivation cycle. Nitrogen fertilizer mainly promotes vegetative growth, promotes chlorophyll production and increases the number of flowers; Phosphate fertilizer mainly enhances the positive growth and development of root system, makes the stem develop tough, resists lodging and promotes flowering and fruiting; Potassium fertilizer can make plants strong, promote the expansion of roots and make flowers more colorful. How to use fertilizer 1? More money: This kind of fertilizer can be bought in Dahan Horticulture Company, with different ingredients, different prices and different service life. Generally, in the process of cultivation, liquid fertilizer roots are irrigated once every 10 day in the early stage and once every 15 day in the later stage (generally 2500 -3000 times). In the early stage, Huaduoduo P30- 10- 10, foliar fertilizer or liquid fertilizer can be used for irrigation to promote nutritional growth. In the middle stage, Huaduoduo P30- 10- 10, P20-20-20, and P 10-30-20 were applied together and mixed. In the later stage, Huaduoduo P 15-20-25 and P 10-30-30 can be combined and used. Of course, domestic growers can also use domestic or imported compound fertilizers with a corresponding proportion of nitrogen, phosphorus and potassium to reduce costs, such as Bathien compound fertilizer and Norwegian compound fertilizer. 2. Application of peanut bran: Peanut bran can be used as base fertilizer or topdressing. The proportion of peanut bran components: 6 peanut bran: 3 peat soil (garden soil): 1 lime. The specific production method of peanut bran is as follows: firstly, peanut bran, peat soil and lime are mixed repeatedly according to the above ratio, watered while mixing, mixed evenly, piled into hills, sealed with film, fermented, turned over after about a week, spread for about a month, broken and dried, then put into snakeskin bags and stored in a dry place for later use. When applying peanut bran, we should pay special attention to the application amount. Generally speaking, each 6-inch pot should put15g, each 9-inch pot should put15g, and it should be placed at the edge of the flowerpot. Some leaves may be damaged to some extent when smeared, but the problem is not very big, just remove them. The application time is generally in the early stage, that is, about 2 months after cutting. 3. Secret fertilizer: The secret fertilizer is a long-acting fertilizer, with the fertilizer effect ranging from 3 to 6 months, and the specification is 30kg/ bag. Each 6-inch pot is about 12- 15g, and each 9-inch pot is about 20g. The application time of secret fertilizer is generally twice, once after direct pot cutting and once after poinsettia turns red. 4. foliar fertilizer: foliar fertilizer is the most effective fertilizer among the above fertilizers. In the management process, foliar fertilizer is generally sprayed every 7- 10 days in the early and middle stages.

water management

poinsettia

Water is the most important factor in plant growth, because fertilizers and nutrients are transported by water. Water management generally follows the principle of "dry thoroughly" according to the size, growth, weather and temperature of Christmas red. When the weather is hot in summer, it is usually watered once every two days and sprayed every morning and afternoon (after 4 o'clock). In other seasons, the watering frequency can be reduced or the watering cycle can be extended. The height of plants is controlled. Poinsettia stems are erect, and some are as high as 1-3m. If they are allowed to grow naturally, they have no ornamental value. Therefore, it is necessary to dwarf and reshape in commercial cultivation in order to achieve a plump and beautiful appearance. Its specific methods include dwarfing and enucleation. 1. Dwarfing treatment: Dwarfing treatment is also a very important link in the process of poinsettia cultivation, and many growers are faced with the problem of how to control the plant height. To control the height of poinsettia, we should control the selection, dosage, spraying period, plant growth, temperature and luminosity of dwarfing agent. Now there are various dwarfing agents on the market, such as CCC, B9, PP333 and paclobutrazol. The above varieties have their own advantages, among which B9 and paclobutrazol are widely used. But no matter which dwarfing agent is selected, it should be used according to the instructions of the agent. If it is ineffective, the dosage can be increased appropriately. Let's talk about the following period of using dwarfing agents: (1), the dwarfing of surviving seedlings after cutting of mother plants or cutting discs is mainly to cultivate strong main stems to prevent vain growth; (2) The main purpose of dwarfing mother plants about one week before cutting is to cultivate strong cuttings and improve the survival rate of cutting; (3) The main purpose of dwarfing cuttings about three weeks after cutting is to prevent the cuttings from growing white; (4) When the internodes of Poinsettia plants increase obviously, dwarfing agents should be sprayed in time; (5) Spraying dwarfing agent during short-day treatment to prevent excessive growth caused by high temperature; (6) Spraying dwarfing agent before the leaves of Euphorbia pulcherrima turn red, because spraying dwarfing agent after turning red will affect the reproductive growth of Euphorbia pulcherrima. 2. Glue tapping: Glue tapping 1-2 times, or up to 3-4 times if necessary, according to the branching and growth of seedlings during the growth period to promote the growth of lateral branches. When the plant height is 30cm, topping is carried out, and 3-4 buds at the lower part are reserved as the first-level lateral branches, and the upper part is cut off. Generally, the whole plant leaves 6- 10 buds, and all other new buds are erased. Sometimes, coring can be accompanied by cutting. Generally, when the cuttings grow to 15-20 cm after survival, the cut plants may have different heights by cutting off the buds. At this time, it is necessary to cut off the high part and unify all the heights. If the formed plants need pruning, the pruned plants should be pruned again, leaving about 5-6 branches and erasing all buds, and the height should be controlled at about 20 cm.

Short-day treatment

poinsettia

Primula is a short-day plant. When the days are short and the nights are long, they begin to differentiate into flower buds and enter the reproductive growth period. The purpose of short-day treatment is to make poinsettia blossom ahead of time and achieve the effect of economic income generation. Generally speaking, short-term treatment methods are similar. Black cloth is used for shading treatment in cultivation. Bamboo is connected vertically and horizontally at a height of about 2 meters in the shade shed, and black cloth can cover it. Pay attention to the following problems during the shading period of black cloth: 1. It needs to be clear that the processing time of different varieties of black cloth is different. Generally speaking, it should be handled 60-70 days in advance. If it is to be sold during the National Day, it should be processed from July 5 to July 20, and the seedling height is generally 12 cm-65438+. 2. Pay attention to the adjustment of temperature: because the temperature is relatively high in summer from July to September, and the temperature will rise sharply when the black cloth is covered. If it is not handled properly, the plants will grow in vain and the flowering period will be delayed. It is best to hang a thermometer in the greenhouse, with the early temperature controlled at 23℃~28℃ and the middle and late temperature controlled at 19℃~22℃. If the conditions do not allow, you can pass. 3. Pay attention to the adjustment of daily treatment time: the treatment time of black cloth should not be too long or too short. Generally, the daily treatment time should be controlled at 3~4 hours. The specific time of our operation is from 5: 00 am to 7: 00 am and from 5: 00 pm to 7: 00 pm, because the temperature is relatively low during this time, plants will not grow in vain. 4. Attention should be paid to dwarfing: when the plants grow excessively at high temperature, dwarfing agents should be used according to the plant growth, which can be treated once every 10~ 15 days, but the concentration should not be too high. It is appropriate to use dwarfing agents for 1000 ~2500 times, but after the leaves turn red. 5, pay attention to fertilizer and water management: watering should be based on the growth of plants, size, humidity and temperature of the medium, it is best to spray water once a day in the morning and evening. In the aspect of fertilizer management, it takes about 10~ 15 days to irrigate more (the choice of fertilizer depends on the plant size) and spray foliar fertilizer once a week. Practice has proved that the short sunshine treatment time of Peter Star is about 45 days, and the short sunshine treatment time of high light and dark red is about 38 days. "Millennium" has strong growth potential, high temperature resistance, short photoperiod and only 42 days of dark treatment.

Long sunshine treatment

poinsettia

As mentioned earlier, poinsettia is a short-day plant. Under the condition of short sunshine, flower buds begin to differentiate and enter the reproductive growth period. Conversely, plants under long sunshine conditions will inhibit reproductive growth and promote vegetative growth. The daily long sunshine treatment time is 3~4 hours, which means that the daily sunshine time should be gradually adjusted from 3 hours to 4 hours with the passage of time. There are two situations for poinsettia to be treated with long sunshine: one is that when the cutting seedlings of that year are used as mother plants in the next year, they should be treated with long sunshine; The other is that the cuttings or mother plants of that year should be kept for long-term treatment when they are sold in the Spring Festival. Here are some problems that should be paid attention to in the treatment of long sunshine: 1. Need to know the time of long sunshine treatment: generally speaking, it can be sold within 60~75 days after the end of long sunshine treatment, so it is necessary to know the delivery time of this batch of goods before making the long sunshine treatment plan. Of course, different varieties of long-day treatment time is not the same. Generally, the long sunshine treatment time is around September 20 every year. Because the photoperiod was shortened after September 2 1, plants began to reproduce and grow in short sunlight. 2. It needs to be clear that the time for changing lamps is generally about 60~75 days before sales. For example, if the lamps are to be sold during the Spring Festival, they should all be replaced before1October 1 1. If it is sold at Christmas, some lamps can be changed without lighting, but they must be changed before 10 10/0 15. For example, Peter Star, the seedlings cut on August 26th every year, start to glow on September 24th, and1October 26th 10 will be ready for shipment during the Spring Festival after the core is picked. Then, before the end of 5438+00 in June, it is advisable to have 3 hours of long sunshine every day, with the mid-term adjustment of 3.5 hours and the late adjustment of 4 hours. The reason is that with the passage of time, the days are getting shorter and shorter, and the long-term sunshine treatment should be longer and longer.

Edit this section of pest control.

Poinsettia is prone to gray mold, root rot, stem rot, leaf spot and other diseases and pests in greenhouse cultivation, and there are many targeted studies at home and abroad. Gray mold mainly occurs in winter, which is the season when poinsettia blooms. Once it is rainy, wet and sunless, it often gets out of hand, which can harm poinsettia inflorescences, bracts, leaves and branches. Generally, water spots appear from tidbits. After that, the lesion was covered with a layer of pathogen meristem robe, and the pathogen continued to spread to the bracts. At the beginning, the bracts faded in water, and then gradually expanded into irregular shapes, and the bacteria spread to the branches, producing yellowish brown to brown spots on the branches. In the later stage, the spots obviously sag downward and become dark brown. In severe cases, the spots are dry and completely lose their ornamental value. The pathogen is botrytis cinerea, which is almost all over the greenhouse. It can feed on dead plant tissues or other organic substances and has a wide range of parasites. It can survive at the temperature of 0 ~ 38℃, as long as there is water. If the greenhouse is too humid, cold and light is insufficient, after 1 ~ 2 days, pathogenic bacteria will produce a large number of robes and begin to infect plant tissues. Root rot and stem rot can infect adult plants, but also in seedbed stage, causing serious losses. Generally, it is more serious in high temperature season, and it is also easy to happen when the water content of cultivated soil is high. In the early days, plants withered. At this time, if you check the stem base, you can see that it is light brown, but the infected plants are not rotten or hydrolyzed. Later, the lesion gradually spread upward, and the wilting phenomenon became more and more serious. The diseased spot on the stem was slightly concave and yellow-brown, and the diseased spot tissue disintegrated in the later stage, which caused the plant to wither and die due to serious water shortage. Sometimes, the whole plant turns yellow in water and eventually rots and dies. White hyphae are seen near the ground, which is more serious. When the root is sick, it often causes root rot, which affects the normal growth of plants in the early stage and leads to death in severe cases. The main pathogens are Phytophthora, Rhizoctonia and Pythium. Rooted cuttings are most vulnerable to Rhizoctonia solani when put into pots, especially when stems are injured or chemical fertilizers are used! When salt accumulates on the surface of the medium; Pythium in poinsettia

Poinsettia appeared when it grew into a plant, and it may have invaded when it was cut. When the environment is suitable for reproduction, it will deteriorate and cause root rot and death. High temperature and excessive irrigation (unfavorable conditions) will cause late blight. Leaf spot mainly occurs in spring and summer, and the disease spots mostly start from old leaves. In the early stage, purple-red to brown spots were produced on the leaves, and the lesions were nearly round to irregular. Later, the lesions gradually expanded, and most of the lesions could heal with each other to form large lesions, and the center of the lesions gradually turned grayish brown in the later stage. In severe cases, the diseased tissue will gangrene, resulting in twisted and dry leaves. The pathogen is Cercospora puleherimaether p., which spreads through rain and wind, and invades through leaf margins or wounds. The pests of poinsettia mainly include whitefly, spider mite, thrips and so on. Adults and larvae of Bemisia tabaci like dense and cool environment. They cluster on the back of the upper leaves of Poinsettia and suck juice with stinging mouthparts, which makes the leaves fade or appear chlorosis spots, which affects photosynthesis and leads to poor plant growth. Honey dew discharged by insects often causes mildew. Adults have a tendency to turn yellow. The eclosion time starts at 6: 00 in the morning, with the highest eclosion at 7-8: 00 and the lowest at night. The first instar larvae are the most vulnerable, followed by newly emerged adults, which are sensitive to chemicals and suitable for spray control. Whitefly usually occurs in large numbers under the conditions of high temperature and low humidity, and the peak period is from late September to late October of 165438+ 10. The best control period is in late September and the application time is 6 ~ 10 in the morning. Tetranychus urticae, also known as red spider, is a common pest in greenhouse. There are more than 20 generations in the whole year, which is serious under the conditions of high temperature, drought and little rain, and the peak periods are March-June and September-165438+1October. Mites or nymphs like to live on the back of old leaves, and the damaged leaves have yellow spots. Insects, eggs, silk screens and secretions can be found by examining the back of leaves. A large number of netting hazards occur, which leads to plant growth stagnation, dry leaves, falling off and plant death. The body length of thrips is only about 1 ~ 2 mm, and its harm can be found on the leaves or flowers of almost all greenhouse plants. But overall, the damage to poinsettia is not very serious. Adults and nymphs are pale yellow or orange, which is harmful to plants with file suction mouthparts. The damaged parts include buds, leaves and flowers. Especially, the young leaves and shoots are the most seriously damaged, which leads to poor plant development. The white markings on both sides of the main veins of leaves can be judged as the damage characteristics of thrips. The damaged leaves cause white or brown markings, and in severe cases, the leaves are twisted and deformed. Flowers are deformed. Yellow armyworm paper is effective for thrips adults, but blue and white armyworm paper is more effective. The key to control whitefly is to avoid a large population. Adult whiteflies are attracted by bright yellow, so yellow sticky trapping paper is very useful in detection. There are many drugs to control whitefly in various places, such as "Pujiaoling" and "Efficient Hero", which can be tried. It should be noted here that before a new drug is used in a large area, a toxicity test must be done to confirm that the dosage used will not cause toxicity to plants before it is used in a large area.

Edit this postpartum treatment

The coming winter festival coincides with the unique and delicate red bracts of poinsettia. Decorate the indoor environment of public places with potted plants or hanging pots, and suddenly the room is full of brightness, showing a warm and happy atmosphere. A few pots adorn the windowsill, balcony or study, red and green, charming and moving. Poinsettia is sensitive to cold and hot wind during storage and transportation, and ethylene will wilt the plant, so silver thiosulfate solution (concentration 0.3 ~ 0.8 mmol) should be sprayed. At the same time, during storage and transportation, the bracts and leaves of poinsettia bend upward, which is mainly caused by the internal accumulation of ethylene. Under the condition of 10℃, the storage and transportation of the package shall not exceed 48 hours until the package is opened. Freezing injury will occur when the temperature is lower than 10℃, and the petiole will bend upward and the bracts will fall off when the temperature is higher than 10℃.