Propagation and Pest Control and cultivation techniques of potted Magnolia

Propagation and Pest Control and cultivation techniques of potted Magnolia

1 biological characteristics

Gentleman orchid is a perennial herbaceous flower, not cold-resistant, but also avoid high temperature and heat, like semi-overcast and humid environment, afraid of both cold and heat. The adaptive temperature for growth is 15 ~ 25 ℃, and the florescence should be controlled at 15 ~ 20 ℃. When the temperature is below 10 ℃, the growth and development of the plant is slow, and the winter temperature can not be lower than 5 ℃. When the temperature is below 5 ℃, the growth and development is inhibited. When the temperature is below 0 ℃, the leaves are frostbitten slightly, and the heavy ones die of the whole plant. When the temperature exceeds 30 ℃, it will force dormancy and lead to short flowering period and light color. Ventilation and cooling should be carried out, otherwise the plants will grow too long and the leaves will be slender and thin. The gentleman orchid requires that the air humidity is 60% ~ 80%, so that the leaves are dark green and neatly arranged in short width; when the humidity is less than 60%, the tender leaves become light, yellow and even wilt, serious until the whole plant wilts and die; the humidity is more than 90%. The stems and leaves grow only; the water content is 20% ~ 40%, and the roots are easy to rot if the soil water content is too large. Loam requires loose, fertile, well-drained, humus-rich slightly acidic sandy soil, and likes ventilated and deep, fertile and loose saprophytic soil. The root of Cymbidium is a stout and well-developed fleshy fibrous root, the leaves are dark green and broad, leathery, the base of the leaves form pseudobulbs, and the leaves are in the shape of a sword and entire. Scape extracted from the foliage, in a semicircular or oblate umbrella-shaped arrangement, flower funnel-shaped. The flowering period is mainly in spring and summer, and the berries are globular, with one to more seeds in each fruit, and the fruit ripening period is about 10 months.

2 methods of reproduction

The propagation of Magnolia in the north is mainly ramet propagation, and the sowing reproduction is common in the south where the conditions are close to the climate of the origin. Take out the mother plant that can be ramified from the basin, remove the persistent soil and the dry root system, separate the joint of the foot bud and the mother plant with tools or manual work, and then spread some plant ash on the wound to dry the liquid to prevent decay, dry for a few hours, and then plant in the pot. Ramet propagation is the most widely used, which can be carried out all the year round, when the temperature can be stabilized at about 20 ℃, and the plant heredity is the most stable.

3 cultivation and management

3.1 Fertilizer

The main fertilizers needed for the orchid are nitrogen fertilizer (rotten bean cake, peanut cake, peanut, sesame, sesame oil residue, castor seed, etc.), phosphate fertilizer (fermented rice paste, bone meal, fish arch, etc.) and potassium fertilizer (charcoal, rice straw, straw ash, rice husk ash, etc.). In accordance with the principle of "thin fertilizer and diligent application", the fertilization of gentleman orchid is mainly organic fertilizer, properly combined with inorganic fertilizer, the fertilizer can not directly touch the root, so as not to burn the root. If we grasp the amount of fertilizer application according to the growth characteristics, we can fertilize more rapidly in spring and autumn, and less or stop fertilizing in summer and winter. At the same time, to observe the effect of fertilization, if the new leaves appear spots and roots turn yellow in winter, it shows that there is too much fertilization, while the narrow, thin and light color of the new leaves is the manifestation of lack of fertilizer.

3.2 watering

Cymbidium likes to be moist and can not be short of water during the whole plant growth period. it has well-developed fleshy roots and a certain amount of water is stored in the roots, so this kind of flower also has a certain degree of drought tolerance. The amount and times of watering should be controlled according to its growth cycle and season, and watering should follow the principle of "dry and wet, no dry, no watering, dry, thoroughly and no leakage". In the case of high temperature and dry air in summer, there should not be a serious shortage of water, otherwise it is easy to cause the basin soil to be too dry, make the leaves yellow, damage the roots of flowers, lead to the germination of new leaves, not only affect flowering, but even cause plant death. It is appropriate to spray foliar and surrounding soil with water every morning or evening in summer to keep the environment cool. Too much watering will cause rotten roots and lead to the occurrence of diseases and insect pests, so keep the basin soil moist in spring and autumn and slightly dry in winter. During the period of pulling arrows, the leaves can not be watered to avoid the occurrence of rotten arrows. Reduce the amount of water properly after flowering, and be careful not to splash water on the flowers to avoid petal decay and shorter flower life.

3.3 Light exposure

Magnolia is a semi-positive, shade-loving flower, likes scattered light, does not require long light time, and grows poorly under strong and weak light conditions. From November to February of the following year, there can be no shading, and from March to October, shading can be chosen according to the light intensity. Place maintenance in a ventilated and shaded place in summer. When exposed to the hot sun, you will get sunburn and inhibit growth. Spring and autumn should cover the strong light at noon, put it indoors in the sunny place in winter, the sun shines for as long as possible, and the weak light and scattered light can prolong the flowering period of the Spring Festival. The orchid has phototaxis. In order to make the orchid beautiful and neat, the plant type should look sideways at a line, face squarely like a fan, and often turn the flowerpot with the change of the position of the sun. There are two ways to arrange the flowerpot in the room: one is to make the leaf parallel to the sunny window, the other is to make the leaf perpendicular to the sunny window, and the effect of the latter is better than that of the former. If the leaves are twisted and crooked, light reshaping should be taken mainly, and artificial mechanical plastic surgery should be assisted.

3.4 selecting and changing pots

In the process of growth, the original pot can not adapt to the further extension of its root system, and the pot used in cultivation should be gradually increased with the plant growth, such as the nutrients in the original soil have been completely absorbed, and the pot needs to be changed. The pottery pot has good air permeability and good cultivation effect. When changing the pot, the diameter of the flowerpot should be similar to the unfolding length of the leaves of Cymbidium, and then the plant depth should be suitable when planted in the flowerpot. When changing the basin, the old, residual and dead roots should be removed, pay attention to protect the root tip from damage, and artificially stretch the root group when planting. Changing pots is carried out in spring and autumn.

3.5 temperature control

The suitable temperature for the growth of Cymbidium is 15 ~ 20 ℃. Too high or too low temperature has a great effect on Cymbidium. When the temperature was higher than 30 ℃, the leaves were thin and slender, and the leaves became shallow, yellow and even wilted. The lowest critical temperature is 0 ℃. If the temperature is below zero, freezing injury may occur and the leaf tip will turn yellow, so temperature management is a very important link in the management of Cymbidium. In summer and winter, the magnolia should take measures to cool down, prevent cold and frost. To control the room temperature in winter, you can increase the temperature through heating equipment such as heating and air heaters. If the temperature does not meet the requirements, you can put the flowerpot on the radiator with a wooden board, otherwise the growth and development of the orchid will be restrained, and even the leaves will be frostbitten. The leaves will be yellowing or "arrow entrapment" phenomenon. It not only affects the ornamental effect, but also is not conducive to the growth and development of Cymbidium. If there is an "arrow clip" phenomenon, it is necessary to increase the indoor temperature. The regulation of the greenhouse in summer can not only reduce the temperature by opening windows, but also spray water on the field and leaves around the potted flowers to reduce the temperature and increase the humidity. In the "arrow drawing" stage, the temperature is higher, and the flowering temperature is about 15 ℃ to prevent the phenomenon of "entrapment". The best temperature difference between day and night is about 8 ℃, which is conducive to running arrows, otherwise the arrows will blossom if they do not reach the appropriate height, and it is easy to form "entrapment arrows".

3.6 Leaf maintenance

Cymbidium is a kind of flower that can be viewed with flowers, leaves and fruits. For Cymbidium grandiflorum, it has the characteristic of "watching leaves is better than flowers". Therefore, attention should be paid to the maintenance of the leaf surface to improve its ornamental quality. Leaf brightness is one of the main indexes. How to make leaf brightness is related to the following factors: (1) to ensure that the root system is developed and not rot, fertilization should be appropriate and reasonable, and the proportion of phosphorus fertilizer and potassium fertilizer in nutritious soil should be carried out scientifically. (2) maintain humidity, pay attention to the wettability of the leaf surface, spray water to the leaf surface every day, preferably fog water potential. In the high humid season in summer, it is sprayed once a day in the morning and once in the evening, in order to reduce the evaporation of water in the leaves. In order to prevent the leaves from growing and elongating in the high temperature climate, water spraying is used to reduce the evaporation of water inside the leaves, reduce the leaf temperature and protect the leaves. (3) there should be enough light, and it is recommended that the light time should not be less than 8 hours in spring and autumn, avoid the destruction of chlorophyll caused by strong light in summer, and increase light as much as possible in winter. Pay attention to the angle between the plant and the sun during daylighting to avoid random tilting of leaves. If the leaves are deformed by daylighting, archery, flowering or fruit-setting, they need to be reshaped in time. (4) observe the situation of the leaf surface, determine whether the plant has occurred diseases and insect pests, adopt corresponding treatment measures, and rescue in time. The leaf surface of Cymbidium is less than 4 in width ratio, the leaf tip is round and blunt, and the leaf vein is obviously the best ornamental state.

4 common problems and pest control

4.1 rotten root

The common causes of root rot are: (1) long-term and massive watering in high temperature environment, which leads to rotting root; (2) excessive use of fertilizer, which leads to root burn and root rot; (3) basin soil does not change for a long time, and the soil is hardened and impervious; root respiration is blocked, which leads to root rot; (4) long-term lack of water leads to root wilting and excessive watering leads to root rot. (5) the immature leaves and other organic fertilizers in the raw soil should be fermented in the basin to produce heat and burn the roots or soil improperly. When the root rot occurs, the main symptoms of Cymbidium are that the leaves become soft and yellow, and the leaves are immersed in water. Corresponding measures should be taken: (1) remove the rotten root from the basin; (2) wash the root with potassium permanganate, disinfect and sterilize, or smear the wound with purple potion, charcoal ash, straw ash and so on; (3) replace the new soil and control the amount of water and fertilize at the same time.

4.2 clip Arrow

The arrow clip shows that the development of the flower stem is too short to open beyond the leaves. It is usually caused by low temperature or improper watering and insufficient fertilization. The suitable temperature for the arrow drawing of Cymbidium is about 20 ℃. If the temperature of the flowering stem is lower than 15 ℃, the growth potential of the flowering stem will be weakened. When the orchid reached the reproductive growth period, the amount of fertilizer needed increased, during this period, fertilizer and water were inappropriate, resulting in poor growth of flower stems in the case of lack of water and fertilizer. The way to prevent the trap of arrows is to raise the soil temperature to about 20 ℃ during the arrow-drawing period and change the soil and basin in time. The water demand of Cymbidium is higher than that of other periods, so it should be watered more, but the soil should not be too wet, and the soil water content should be 30%. When watering, do not pour water between the two rows of leaves, enter the reproductive growth period to increase the number of fertilization, increase the application of liquid fertilizer.

4.3 sunburn

Magnolia is easy to grow under scattered light, and exposure to sunlight in summer will kill leaf cells and cause sunburn. Therefore, it is appropriate to put it in a shaded, moist and ventilated place outdoors. Avoid direct sunlight indoors.

4.4 Infertility

The main reason for not blooming is related to the light time. The light time of orchid in the origin is less than 13 hours, while that of indoor cultivation is much more than 13 hours because of normal light and lighting and other factors. To prevent the orchid from blooming, the light time should be controlled at about 13 hours. The phenomenon of flowering without fruit is mainly pollination. The pistil stigma of Magnolia is higher than the anther of stamens. If the flowering season is indoor in winter and spring and there is no insect pollination, artificial pollination is needed to help fruiting [Yoshanhua Yao].

4.5 disease damage

The common diseases of Cymbidium are soft rot, leaf spot and anthracnose. Prevention and control methods: (1) strengthen environmental hygiene and maintenance, change soil in time, pay attention to soil disinfection, wash fleshy roots with clean water during soil change, and then put them on the basin after drying; (2) pay attention to ventilation and light transmission to avoid inadequate fermentation of nutritious soil and fertilizer, unsatisfactory soil disinfection and mechanical damage. (3) optional spraying agents before or at the initial stage of the disease: 500-700 times of 50% anthrax Fumei wettable powder, or 600-800 times of 75% chlorothalonil wettable powder; (4) pay attention to fertilizer and water management, improve growth potential and enhance disease resistance.

4.6 insect damage

There are not many kinds of common pests in Cymbidium, mainly scale insects, snails and earthworms. When a small amount occurs, you can use a soft brush, rags or bamboo pieces to gently remove and wipe off with cloth dipped in kerosene, and then rinse with clean water. 3-5 times Baumedushi sulfur mixture can be sprayed once before germination, and 80% dichlorvos emulsion can be sprayed with 1 000 times of dichlorvos emulsion in nymph stage. For earthworms, 50% dichlorvos emulsion dilution can be used.