The choice of soil is very important for the growth and development of rhododendron. There are many ways to mix cultivated soil for planting rhododendron, which varies with cultivated varieties, but the following conditions must be met: looseness, smooth drainage, good ventilation, rich acid soil and humus, and sufficient base fertilizer. Rhododendron usually grows vigorously in acidic loam. If it lives in alkaline soil, it will soon die of yellow leaf failure. Rhododendron is considered as an indicator plant of acidic soil. Generally speaking, humus soil belongs to acidic soil, and pine humus soil is the best, which is an ideal culture soil for planting rhododendrons. You can dig under the pine and cypress forests in mountainous areas, or you can plant a variety of pines and cypresses in the courtyard and borrow soil underground. Before use, add appropriate amount of sulfur powder and alum to improve its acidity before use. The soil with high humus content is most suitable for the growth of rhododendron. There are many humus, which can replenish nutrients in the soil in time, improve the soil structure, and make the soil retain water, fertilizer, ventilation, heat absorption and heat preservation. It can also reduce the harm of toxic substances in the soil and promote the root system of rhododendron to spread everywhere.
Black Mountain Mud is a new product produced in Tongguan Mountain, Yixing, Jiangsu Province and Fenghua, Zhejiang Province. It is most suitable for the growth and development of rhododendrons and is widely used everywhere. Culture soil can also be homemade. Take 2 parts of weathered mountain surface soil, fallen leaves 1 part, and dry dung of herbivores 1 part, mix them 1 year, and use them after screening off impurities. 3 parts of mountain bark soil, 3 parts of horse manure, 3 parts of deciduous weeds, and human manure 1 part can also be piled in layers, and screened for later use after 1-2 years. The prepared culture soil should be stored indoors to prevent the fertility from being reduced due to sun and rain.
What should I pay attention to when turning over azaleas?
Rhododendron cuttings should be put in flowerpots to survive. Pottery pots with good air permeability are the best, followed by purple sand pots, glazed pots and porcelain pots are the worst. Pay attention to the size of the flowerpot when serving, and avoid using large pots for small seedlings. If the pot is too big, the soil won't last long, the ventilation is not good, and the roots can't easily reach the pot wall, which will affect the development of seedlings. Generally, cutting seedlings can choose a pottery pot with a diameter of 10 cm, and then turn it into a flowerpot with a diameter of 15 cm after one year. Pay attention to the drainage layer when putting the basin. Cover the drain hole with ceramic tile first, then put in 1/3 coarse soil particles and add a little fine soil. Then put the rhododendron seedlings in, straighten the seedlings with one hand and put them in pots with the other. Pay attention to fill the soil only 2 cm below the mouth of the basin, and don't fill it too full for later watering. Finally, tamp the periphery of the basin and shake the flowerpot to make the basin surface smooth. After planting, water it once with a watering can. Be sure to pour when boiling water until water seeps from the bottom of the basin. If watering is not thorough, only grasping the decayed layer and not wetting the inner layer will dry up the potted flowers.
There are two situations in which cuckoo turns over the pot. First, the seedlings grow up and the roots are full of pot soil, so it is necessary to expand the extension of root health. Usually, pay attention to whether the drainage holes at the bottom of the basin have roots sticking out. If there is, turn the pot upside down and turn the plants from a small pot into a big pot. Second, after potted flowers grow for 2-3 years, the contents of potted soil are exhausted. In order to supplement nutrients and improve soil, potted soil should be replaced.
Rhododendron flowerpots are generally turned over after climbing flowers in autumn or before pregnancy. When turning over the basin, remove some soil and pay attention to pruning the roots with sharp scissors. Old roots refer to those roots that are blackened and withered due to poor growth. However, it should be noted that when the seedlings turn over the pots, the roots cannot be trimmed. When turning over the pot, you should pay attention to the soil ball at the root. After putting the pot away, you should also pay attention to watering it thoroughly for the first time and let it dry thoroughly in the next few days. If it is too wet, the root incision will rot. Generally, only when new roots grow can normal irrigation be carried out. If you turn over the pot in autumn, it is best to turn it over in June of 5438+ 10. Although azaleas like to be cool, they should keep warm after turning over the pots in winter. If there is no shed, you can set up a shed in a ventilated place facing south to the sun, covered with plastic film, and spend the winter safely. Generally, the seedlings of Rhododendron in long pots turn once a year, and the big rhododendron turns every 2-3 years 1 time.
How to water azaleas?
Watering azaleas is a very important job. Because the root system of Rhododendron is weak, it is resistant to waterlogging and drought. Too dry or too wet is not good for plant growth, so special attention should be paid to controlling water quantity. If there is a lack of water during leaf development, the leaves of rhododendron will turn yellow and curly, and they will die if they are not well dried. If there is no water when flowering, the petals will be soft and shriveled, the flowers will droop, the colors will not be bright, and even wither and die. Therefore, water should be watered according to the weather, rain, dry and wet air, water content of basin soil, etc.
Watering time should be in the morning and evening, especially in hot summer, not at noon. Because the roots are stimulated by cold water, the flowers will be hurt. The principle of watering is not to dry, to water thoroughly, and not to water half. Spring and autumn are the growth, flowering and budding periods of rhododendron, so the water supply should be appropriate, but it is not advisable to water too much at flowering stage, which will make the flowers wither early. Generally, water 1 time every 2-3 days in spring and autumn. In summer, new branches sprout and grow vigorously, consuming a lot of water. In addition, the temperature is high and the air is dry, so it needs to be watered 1-2 times a day. If it doesn't rain for a few days and the air is dry, you should spray water on flowers and leaves with a fine-eye watering can, and also spray some on the ground around the flowerpot to increase the air humidity. In case of yellow plum days or rainy days, stop watering and drain the accumulated water in the basin in time. Although the temperature drops in autumn, the air is dry and the evaporation is still very large, so it is necessary to water the basin soil frequently to keep it moist. When flower buds differentiate, it is necessary to properly control the amount of water to promote the formation of flower buds. After 10 months, the watering amount should be reduced as appropriate, the water content of branches is low, and the plant tissue is fully developed, which can increase the cold resistance. At this time, keep the basin soil slightly moist.
How to treat the water quality when watering azaleas?
Water azaleas, pay special attention to water quality. It is best to use natural rainwater as water, because natural rainwater does not contain impurities such as drugs and bleaching powder. Followed by river water and pond water, and tap water again. Tap water is purified soft water, which contains chemicals such as bleach, liquid chlorine and alum. If this water is used for a long time, the alkalinity in the basin soil will gradually increase, which is not conducive to the growth of azaleas. Therefore, the water quality must be treated before use. The treatment method is acidification. Water that is neutral or alkaline to water quality should be prepared into acidic water. The usual method is to acidify water with ferrous sulfate (copperas) and vinegar. If the water quality is too alkaline, ferrous sulfate and vinegar can be used together, and the specific dosage can be prepared according to the pH measurement of water, ferrous sulfate and vinegar. The simple method is to irrigate for a long time with an aqueous solution containing 0. 1%-0.5% ferrous sulfate, or sprinkle a little ferrous sulfate on the basin surface for 10- 15 days. You can also pour an aqueous solution containing 0.5%- 1% vinegar every15 days. You can also use tap water and well water that has been dried. Drying water can reduce the harm of harmful ions in tap water; It can also improve the water temperature of well water and eliminate the temperature difference between water and basin soil, which is beneficial to root absorption. When tap water is used, 0. 15% ferrous sulfate should also be added. When watering, it is more advantageous if it can be watered in turn with the decomposed fertilizer solution. Because the use of these two kinds of water together can keep the acidity of the basin soil and supply certain nutrients, which is suitable for the growth of azaleas.
How should azalea be fertilized?
Rhododendron is a flower that doesn't need big chemical fertilizer. If the fertilizer is applied too much or too thick, it is not good for its growth. But this does not mean not to fertilize, but to let it bloom a lot, or to apply some fertilizer at the right time. Therefore, flower cultivation experts summed up eight words of fertilization experience: "less dry fertilizer, dilute liquid fertilizer." This is very suitable and worthy of reference for flower growers. Generally speaking, 1. Two-year-old seedlings don't need fertilization, because humus soil contains enough fertility to meet the needs of seedling growth and development. For 2-3-year-old plants, pancake fertilizer or alum fertilizer can be applied every 10- 15 days from late spring or hot summer. For plants over 4 years old, about 20 grams of dry cake fertilizer can be applied in spring and autumn every year. In mid-June, available phosphorus and potassium fertilizer can be applied once to promote flower bud differentiation. Fertilization can be stopped after June. After the flowers wither and the new branches grow, liquid fertilizer with a slightly higher concentration can be applied once, but it must not be applied too thick, let alone raw fertilizer, otherwise the root system will be damaged. In summer, excessive fertilization will make the old leaves fall off and the new leaves turn yellow. It is particularly noteworthy that the deviation of azaleas planted at home is not a lack of fertilizer, but an injury caused by excessive fertilization. If the leaves turn yellow due to excessive fertilization, immediately stop fertilization, dig out dry fertilizer, water more, and wash away the fertilizer in the accumulated soil. After watering, move to a ventilated place for maintenance, and some need to be washed twice. This will gradually grow normally after half a year.
If there is no abnormality in summer, azaleas will start their second vigorous growth period after beginning of autumn. In this short period of time, it is possible to supply 1-2 times of phosphate fertilizer dilute solution to meet the needs of plant growth and bud pregnancy. After each fertilization, water is poured every two days, and the soil is loosened once, so that the basin soil is fully ventilated. After winter, as the weather gets cold and plants stop growing, fertilization should be stopped immediately. If you don't stop fertilizing and let plants grow tender leaves, it will make it difficult for rhododendrons to overwinter, so don't be careless.
How to trim and reshape azaleas?
Rhododendron has a strong ability of germination and regeneration. Every 1-2 years, after the flowers wither, it is necessary to change a flowerpot that is larger than the original one and put on new culture soil. Experienced florists often combine pruning and shaping when changing pots, and consciously prune a beautiful tree. When cutting sulfur, close branches, cross branches, twigs, drooping branches, creeping branches and insect branches should be cut off, which is not only for the beauty of the tree, but also for improving ventilation and light transmission conditions; Save nutrients, make the main branches strong, so as to sprout new buds as soon as possible, so as to achieve the goal of more flowers, bigger flowers and brighter colors in the coming year.
After azaleas are in full bloom, their residual flowers often last for a long time and consume a lot of nutrients. In order to prevent nutrients from being consumed in vain, the residual flowers should be picked in time to supplement nutrients for the needs of new germination technology. Besides, Xia Juan, who has a shorter plant, has many branches. Every spring, many branchlets will grow on the branches of the roots. In order to concentrate nutrients on the main branches and flowers and make them grow faster and bigger, these branchlets should also be cut off in time. If there are too many flowers, remove all the branches except each branch with a length of 1. What kind of trees to prune can be decided according to your own preferences, such as umbrella, circle, semicircle, pagoda, square and so on. You can choose at will and then trim it deliberately.
How do azaleas propagate by cutting?
Rhododendron can be propagated by cutting, grafting, layering, dividing plants, sowing and other methods, among which cutting is the most commonly used method with the largest reproduction; The layering seedling is the fastest and the grafting propagation is the most complicated. Only varieties that are difficult to survive by cutting are grafted, and cultivated varieties are mainly used for sowing.
Cutting propagation, it is best to use a new shallow pottery jar with a diameter of 20 cm, because it is breathable and easy to take root. The substrate can be cultivated soil mixed with 20% humus garden soil, 40% horse manure chips and 40% river sand. Cutting time is best in spring (May) and autumn (65438+1October), when the temperature is between 20-25℃, which is most suitable for cutting. When cutting, select the semi-lignified and robust branches of the year as cuttings and press the knife with the daughter-in-law. Cut 6- 10 cm from the node, and the incision should be smooth and tidy. Cut off the lower leaves, leaving only 3-4 leaflets at the top. Buy 1 Vitamin B for injection12. After unsealing, soak the strips in the medicinal liquid, take them out and dry them for a while before cutting. Before cutting, the soil in the pot should be sprayed with a watering can the day before, but not too much. The next day was just wet, which was most suitable for cutting. The insertion depth is 3-4 cm. When inserting, first leave a hole in the soil with chopsticks, then insert the cuttings, compact them by hand, let the pot soil fully contact with the cuttings, and then water them again. After inserting, it is best to cover the flowerpot with a plastic bag, tie the bag mouth tightly with a belt, open it when watering is needed, and tie it tightly after watering. The cut flowerpot should be placed in direct sunlight, and the cut flowerpot soil should be sprayed with water for 65,438+00 days every day, except in rainy days, 65,438+0 times in cloudy days and twice in dry climate, but the amount of water sprayed should not be too much every day. After 10, be sure to keep the soil moist. Shade it for 4-5 weeks and let it gradually receive some sunshine until it germinates. It usually takes about 2 months to take root. After that, it only needs to be shaded for 2-3 hours at noon, and the rest of the time can be exposed to light, so that it can make its own nutrients in its photosynthesis.
How do azaleas propagate in layers?
Rhododendron layering propagation is also one of the commonly used propagation methods, generally using high-tech layering. Rhododendron layering is often carried out in April-May. The specific operation method is as follows: firstly, take 2-3-year-old robust branches from the potted Rhododendron mother plant, cut off a circle of branch bark with a width of about 1 cm at the top of the branches with a sharp knife, gently peel off the sieve tube of phloem, cut off the downward transportation channel of leaf organic matter, and make it gather, thus accelerating cell division and forming tumor-like protrusions. Then loosely wrap it in rectangular plastic film for two times, tie it with a string at the lower end of the circular cut 2-3 cm, leave the shape of a Zhang Kaicheng trumpet at the upper end of the plastic film, then fill it with wet soil and a little moss, tie the upper end of the bag, and move the flowerpot to a place out of direct sunlight for daily management. When watering, water should be sprayed on the leaves to make the water flow down the branches and slowly penetrate into the bag, and the soil in the bag should always be moist, so as to facilitate the wound healing on the branches and make them grow new roots as soon as possible. After about 3-4 months, when the roots grow to 2-3 cm long, you can cut off the branches and plant them in a new pot of soil.
How are azaleas sown and propagated?
Sowing is sexual reproduction. Because the seed setting rate of natural hybridization is very low, artificial pollination is generally needed to improve the seed setting rate of rhododendron and obtain more seeds. The main method is to select healthy female parents with good growth and beautiful colors when azaleas are in full bloom, move them to the greenhouse, select 3-4 flowers with large flowers and early flowers in each pot, remove stamens and new buds near the flowers, and concentrate on nutrition. When mucus appears on the flower stigma, dip the pollen of the male parents with a new brush and apply it several times. After pollination for one week, move the flowerpot outdoors to strengthen water and fertilizer management. After about 5-6 months of growth and development, the fruit of LL-65438+February gradually changed from cyan to brown, and the seeds were mature. Take it off immediately, dry it in the shade, keep it clean and put it in a cool and ventilated place.
Rhododendron seeds are too small to be stored for a long time, otherwise the germination rate will be low. If it is an evergreen rhododendron seed, sow it in a flowerpot in the greenhouse; If it's a deciduous rhododendron seed, it can be planted next spring.
Sowing pots should be shallow soil pots. For the sowed soil, loose topsoil with moss can be dug on the sunny hillside, and stone chips can be removed. It is best to spray it once with 40% formalin and 100 times water diluent, and dry it after disinfection. You can also steam in steam 15-25 minutes for disinfection, and then dry in the sun for later use. Before sowing, water the shallow pot, spread a layer of carbon chips about 2 cm on the bottom, then spread a layer of 5-6 cm thick sterile soil, scrape it flat, slightly compact it, then evenly distribute the seeds on it and gently press it. Don't spray water with a watering can, it is best to soak it in a water pot. Cover it with a piece of glass and move it to a warm room. When the surface of the basin soil is dry, you can spray some water in the form of mist, but not too much. As long as the basin soil is always kept moist.
After sowing, it usually takes 5-6 weeks to germinate. When the seedlings grow 2-3 true leaves, they can be gently squeezed out with small bamboo pieces and planted in other pots. Don't plant it too closely, plant it sparsely. After planting, shade with reed mats. , in order to avoid direct sunlight or let the rain wet them. Do not apply fertilizer when the seedlings are young, and apply thin fertilizer when the seedlings grow to nearly 10 cm in the second year; Generally, in the late spring and early autumn of the second year, individual plants can be planted separately. By the third year, when the seedlings grow to a height of 20 cm, if cultivated well, several seedlings can blossom.
What are the common diseases of rhododendron? How to prevent it?
The diseases of rhododendron mainly include root rot, brown spot, black spot, leaf blight and iron deficiency chlorosis.
After Rhododendron suffers from root disease, its growth potential is weak, its leaves are wilting and dry, its root surface is covered with waterlogged brown fields, it is severely soft rot, gradually decays and peels, and its xylem turns black. This disease is most likely to occur in high temperature and high humidity environment.
The prevention method is to strictly disinfect Pei 10 soil before turning over the basin, so as to keep the soil loose and moist, make it have good permeability and avoid water accumulation. If plants are found to be sick, they should be treated in time. During treatment, the diseased plants can be washed with 0. 1% potassium permanganate aqueous solution or 2% ferrous sulfate, and then washed with clear water and put on the pot again. It can be cured by spraying 70% thiophanate wettable powder with 1000 times of water into the basin soil.
Brown spot is the main disease of rhododendron. At the early stage of the disease, small brown spots appeared on the leaves, which gradually developed into irregular large spots. Many black or grayish brown spots were produced on the diseased spots, which made the damaged leaves yellow and fall off, affecting the flowering in the current year and the development of flower buds in the next year. This disease often occurs when the humidity is high in the rainy season.
The treatment method is to ventilate plants at ordinary times, not to make the humidity too high, and to increase the application of organic fertilizer and nitrogen, phosphorus and potassium mixed fertilizer to enhance the anti-infection and growth ability of plants. If the diseased leaves are found, they should be removed in time and burned centrally. Spraying 0.5% Bordeaux solution or 0.4 baumeishi sulfur solution at the initial stage of onset, and adding 4% flour to increase adhesion. Leaf spot and black spot can also be treated in the same way.
Iron deficiency chlorosis usually occurs in alkaline soil areas. When the disease is mild, only plants appear late green. In severe cases, it can make all leaf tissues yellow and the leaf edge scorch. When the disease occurs, it is most obvious on the leaves at the top of the plant, which is generally caused by iron deficiency in the body.
The prevention method is to change the nature of iron deficiency in soil and reduce soil alkalinity. Applying more organic fertilizer to transform clayey soil. Plants with iron deficiency can be directly sprayed with 0.2%-0.3% ferrous sulfate solution. You can also poke several holes in the soil around the plants with a depth of 15cm, and slowly inject 1: 30 ferrous sulfate aqueous solution to fill up the holes, so as to increase the acidity of the soil and reduce the alkalinity.
The occurrence and environmental conditions of rhododendron black spot disease are similar to those of brown spot disease, and similar measures can be taken to control it.
What are the common pests of rhododendron? How to prevent it?
The common pests of rhododendron are: red spider, legion worm, aphid, short-bearded snail and so on. Although the red spider is small, it does serious harm to rhododendrons. High-rise buildings with azaleas are most prone to this pest.
The control method is artificial killing. Spraying 5% sulfur mixture, or throwing walnut leaves, central bamboo leaves and green bamboo leaves into pieces and soaking them into liquid, diluting them with water, and spraying dichlorvos 1000 letter water are also good insecticidal methods.
The adults of armyworm are small and flat, about 4 mm long and black, which is the most harmful pest to rhododendron evergreen. It often sucks the leaf liquid behind the leaves, and yellow and white spots appear on the damaged leaves, which makes the leaves fall off, causing the tree to be weak and affecting its growth and flowering. Rhododendrons in greenhouses are prone to this kind of insect.
The prevention and control method is mainly to spray with drugs. 90% trichlorfon 1000 times, 40% omethoate EC 1500 times or 50% chlorpyrifos emulsion 1000- 1500 times can be sprayed.
Aphids mainly harm the young branches and leaves of rhododendron, which can make the leaves lose their green color, shrink and become hard and brittle, unable to absorb nutrients and affect flowering.
The control method is to pay special attention to aphids in wintering period at ordinary times. After winter, plants can be sprayed with 5-degree sulfur mixture to eliminate overwintering eggs, shovel weeds beside flowers and eliminate insect sources. In the period of aphid damage, 40% dimethoate or omethoate is added with 1200 times of water to make a solution, and it can take effect after 3-4 times of continuous spraying.
Short beard e is one of the important pests of rhododendron, which often sucks juice near the main vein of the leaf back, resulting in many oil fields on the leaf back and eventually leading to leaf shedding. This insect is obovate, with a body length of about 0.3 mm, a flat body with red, dark red and wood red, irregular black spots on the back and irregular black patches on the side. This insect is most common in summer when it is hot and dry, and then the rainfall decreases for a long time.
The control method is 1 0. Spray Bomei 0.5-degree sulfur mixture 1 time in the middle and late June, and spray1time in the early spring of March, and the effect is also good.
I don't know if it's detailed enough, hehe
Hope to adopt ~
References:
He Jiong horticulture http://www.guiheyy.com.
Hope to adopt ~