Handbook of Basic Knowledge of Home Flower Growing

　Some netizens asked if there is any one-size-fits-all knowledge about family flower cultivation. Here are some must-knows about family flower cultivation and a handbook of family flower cultivation knowledge. There is a lot of knowledge about family flower cultivation. First, let's introduce the basic knowledge of family flower cultivation!

　　1. What categories are flowers divided into?
　　Known as the "Mother of World Gardens", China has rich flower resources and a wide variety of species. In order to facilitate cultivation, management and utilization, it is necessary to understand the classification of flowers. Due to different classification bases. Therefore, the classification methods are also different. According to the morphological characteristics of flowers, flowers are usually divided into two categories: herbaceous flowers and woody flowers. Herbaceous flowers with soft stems and hard stems are called woody flowers. According to the growth habits and morphological characteristics of flowers, they can generally be divided into herbaceous flowers, woody flowers, succulent flowers and aquatic flowers. Herbaceous flowers can be divided into annual and biennial grass flowers, perennial flowers, bulbous flowers and lawn plants according to their growth and development cycles. Woody flowers can be divided into trees, shrubs and vines according to the height of their trunks and the size of their crowns. Succulent flowers have fleshy stems and leaves, and store abundant water in their bodies. Some of their leaves degenerate into needle-shaped thorns or feathers, with peculiar shapes, so they form their own category in horticultural cultivation. Aquatic flowers grow in water and swamps all year round. Most of them are perennial plants. According to the classification of ornamental parts, flowers can be divided into flower-viewing types (mainly for viewing flower color and flower shape, such as chrysanthemums and roses), leaf-viewing types (mainly for viewing leaf color and leaf shape, such as croton and variegated taro), fruit-viewing types (mainly for viewing fruit, such as kumquat), stem-viewing types (mainly for viewing branches and stems, such as the single tree and mountain shadow boxing, etc.) and bud-viewing types (mainly for viewing buds, such as silver willow). According to their uses, flowers can be divided into cut flowers (such as carnations, calla lilies, etc.), indoor flowers (such as Clivia, Monstera, etc.), garden flowers (such as roses, chrysanthemums, etc.), medicinal flowers (such as peonies, honeysuckle, etc.), spice flowers (such as white orchids, jasmine, roses, etc.) and edible flowers (lilies, daylilies, pomegranates). In addition, based on the climatic conditions of the flowers' place of origin and their natural distribution, flowers can be divided into tropical flowers, subtropical flowers, warm temperate flowers, temperate flowers, subarctic flowers, alpine flowers, etc. This classification method can reflect the habits of various flowers and the conditions that need to be met for their growth and development during cultivation.

　　2. What are the benefits of growing flowers?
　　Flowers, with their gorgeous style, decorate nature exceptionally beautifully and give people a beautiful enjoyment. Growing flowers can enrich and adjust people's cultural life, add fun, cultivate temperament, and improve health; it can also increase scientific knowledge and improve cultural and artistic literacy. Growing flowers can beautify the earth, protect and improve it, purify the air, and enable people to work and study in a beautiful environment, making life better. Growing flowers is not only for viewing, but also has many important economic values. Flowers are an important part of Chinese herbal medicine. Honeysuckle, chrysanthemum, winter plum, hibiscus, azalea, rose, lotus, etc. are all commonly used Chinese herbal medicines. Fragrant flowers are widely used in food, light industry, etc. For example, osmanthus can be used as food spices and wine, jasmine, white orchid, daidai, pearl orchid, etc. can be smoked tea, and chrysanthemum can be used to make high-end food and dishes. White orchid, jasmine, rose, winter plum, daffodil, etc. can be used to extract essence. Growing flowers can also exchange foreign exchange and accumulate funds. For example, rose oil, a high-end essence extracted from roses, is called "liquid gold" in the international market, and its value is more expensive than gold.

　　3. What are bulbous flowers?
　　Bulbous flowers refer to perennial herbaceous flowers with metamorphosis of underground stems or roots and spherical or shaped. According to the morphological structure of their underground stems or roots, they can be roughly divided into five categories: (1) Bulbs. The underground stems are scaly. Those with a papery outer skin are called scales, such as tulips, daffodils, amaryllis, etc.; those without skin outside the scales are called skinless bulbs, such as lilies, etc. (2) Corms. The underground stems are spherical or oblate, with a leathery outer skin, such as gladiolus, freesia, etc. (3) Rhizomes. The underground stems are enlarged and root-like, with obvious nodes on them, and new buds grow at the top of the branches, such as canna, ginger flower, lotus, water lily, hosta, etc. (4) Tubers. The underground stems are irregular blocks or strips, such as calla lily, cyclamen, gloxinia, tuberose, etc. (5) Tubers. The underground taproot is enlarged and block-shaped, and the root system grows from the end of the tuber, such as dahlia, etc.

　　4. What is the relationship between temperature and flower cultivation?
　　Temperature is an important condition for the survival of various flowers. No matter how suitable other environmental conditions are, if there is no suitable temperature condition, flowers will find it difficult to survive. Each flower has its optimum temperature, maximum temperature and minimum temperature for growth and development. According to the temperature conditions in the place of origin of the flowers, flowers can be roughly divided into high temperature, medium temperature and low temperature categories. (1) High temperature category. Such as Milan, poinsettia, cineraria, gloxinia, fuchsia, etc. When cultivated in North China, the minimum room temperature in winter should be kept above 12℃. (2) Medium temperature category. Such as white orchid, jasmine, hibiscus, geranium, etc., the room temperature in winter should not be lower than 5℃ (3) Low temperature category. Such as oleander, osmanthus, kumquat, daidai, cycad, etc., the room temperature in winter should not be lower than 0 degrees. If the temperature is too high or too low, the normal physiological activities of flowers will be destroyed, growth will stop, and in severe cases, the whole plant will die.

　　5. What effect does light have on the growth and development of flowers?
　　Light is the energy source for flowers and plants to produce nutrients. Without light, photosynthesis cannot take place, and the growth and development of flowers will be seriously affected. Most plants can only bloom and grow luxuriantly under sufficient light conditions. Different types of flowers have different requirements for light. A flower proverb says: "Shadow camellia, sunny peony, semi-shade and semi-sun four-season orchid". According to the different requirements of flowers for light intensity, flowers can be roughly divided into positive flowers, neutral flowers and negative flowers. (1) Positive flowers. Most flowers and fruit-viewing flowers are positive flowers, such as magnolia, rose, pomegranate, plum blossom, crape myrtle, citrus, etc. There are also a few positive flowers among foliage flowers, such as cycads, palms, croton, etc. Most aquatic flowers, cacti and succulents are also positive flowers. All positive flowers like strong light and cannot tolerate shade. If there is insufficient sunlight, the branches and leaves will grow too long, the tissues will become soft and weak, the leaves will become pale and yellow, it will be difficult to bloom or bloom poorly, and they will be susceptible to diseases and insect pests. (2) Negative flowers. They grow well in shaded environments, such as asparagus fern, camellia, azalea, hosta, green radish, evergreen, ivy, gloxinia, monstera, begonia, etc. If they are exposed to strong light for a long time, their branches and leaves will turn yellow, their growth will stagnate, and in severe cases, they will even die. (3) Neutral flowers. They grow well in sunny conditions, but they will not need to be shaded in principle when the light intensity is high in summer, such as osmanthus, jasmine, white orchid, hydrangea, etc. In summary, various flowers have different requirements for light, and even the same flower has different requirements for light at different stages of growth and development. The amount of light required by seedlings can be gradually increased, but the positive chrysanthemum requires short-day conditions to form flower buds.

　　6. What effect does light have on flower bud differentiation?
　　The purpose of growing flowers is to make them bloom more flowers, and light is the most effective external factor to promote flower bud formation. On the same flower, branches that receive sufficient light will have more flower buds, while branches that receive insufficient light will have fewer flower buds. When there are many sunny days in summer, flowers receive sufficient light, and there will be more flowers in the next year. Generally speaking, flowers can photosynthesize under the temperature of 10-35℃, and the most suitable temperature is 20-28℃. According to the requirements of flowers for the length of light duration, flowers can be divided into three categories: (1) Long-day flowers. Generally, flowers that need more than 12 hours of sunlight per day to form flower buds are called long-day flowers. Many flowers that bloom in spring and summer are long-day flowers, such as irises, asters, and impatiens. (2) Short-day flowers. Flowers that need less than 12 hours of sunlight per day to form flower buds are called short-day flowers. Poinsettia and chrysanthemum are typical short-day flowers. They can only grow under long-day conditions in summer, but cannot differentiate into flower buds. After autumn, when the light intensity is reduced to 10-11 hours, flower bud differentiation begins. (3) Medium-day flowers. Flowers whose flower bud formation is not strictly required by the length of daylight are called medium-day flowers. For example, calla lily, carnation, zinnia, rose, hibiscus, etc., they have no obvious response to the length of light intensity and can bloom all year round as long as the temperature is suitable.

　　7. What effect does water have on the growth and development of flowers?
　　Water is a necessary condition for the growth and reproduction of flowers. It has a great impact on the growth and development of flowers. Because water absorption exceeds consumption, the flowers have too much water in their bodies, which makes the plants particularly tall and thin, and their resistance to cold and stress is weakened. If there is too much water for a long time, it will cause root rot, leaf fall, and even death. Water absorption is less than consumption, and the flowers will wilt due to lack of water. Severe water shortage will cause the flowers to wither and die. There are many varieties of flowers, and their water requirements are also different. Even the same flower has different water requirements at different stages of its growth. According to the different water requirements of flowers, flowers can be roughly divided into three categories: xerophytes, aquatic plants, and mesophytes: (1) Xerophytes. Such as plum blossoms, crape myrtles, crabapples, hollyhocks, nandina domestica, and succulent flowers are relatively drought-resistant. (2) Aquatic flowers. Such as lotus, water lilies, calamus, water bamboo, etc. (3) Mesophytes. Flowers that can grow well in moist soil. Most flowers belong to this type, such as magnolia, white orchid, winter plum, peach blossom, camellia, bauhinia, etc.

　　8. What effect does air humidity have on flowers?
　　Most of the water needed by flowers comes from the soil, but air humidity also has a great impact on the growth and development of flowers. If the air temperature is too high, it is easy to cause the branches and leaves to grow too long, the petals to rot and fall, and it is easy to cause the spread of pests and diseases. If the humidity is too high during the flowering period, it will hinder flowering and affect fruiting. If the air humidity is too low, the flowering period will be shortened and the color of the flowers will fade. If the air is dry for a long time, the southern flowers will grow poorly and affect flowering and fruiting. The climate in the north is dry in winter. If the indoor flowers are not kept at a certain humidity, some flowers that like moisture will often have pale yellow leaves and dry leaves. According to the different requirements of different flowers for air temperature, you can use methods such as spraying branches and leaves or covering them with plastic film to increase air humidity and create humidity conditions suitable for their growth. Orchids, begonias, monstera and other moisture-loving flowers require the relative humidity of the air to be no less than 80%; jasmine, white orchid, hibiscus and other medium-humidity flowers require the air humidity to be no less than 60%.

　　9. Why do flowers die from excessive watering?
　　When potted flowers are watered too much, the water fills the soil gaps, and the air in the soil is replaced by water. At this time, the outside air cannot enter, resulting in soil hypoxia, root respiration is hindered, physiological functions are reduced, and the root system's ability to absorb water and fertilizer is hindered. At the same time, due to the lack of oxygen in the soil, aerobic bacteria with the function of decomposing organic matter in the soil multiply and become active, increasing the acidity of the soil. Due to the wanton activities of butyric acid bacteria, a series of toxic substances such as hydrogen sulfide and ammonia are produced, which directly poison the root system. At the same time, due to the lack of oxygen, the plants consume a large amount of soluble sugar in the body and accumulate too much alcohol and other substances, which greatly reduces the photosynthesis, and finally causes the flowers to die of hunger. In the practice of flower cultivation, it is often seen that due to excessive watering, the roots of flowers turn black and rot, and the flowers are "drowned". Therefore, when cultivating flowers, pay attention to the right amount of watering.

　　10. What are the harms of insufficient watering of potted flowers?
　　Because potted flowers have little soil and little water storage, they need to pay attention to frequent water replenishment during the growing season to ensure the normal growth of flowers. If the water supply is insufficient, the leaves and petioles will shrink and droop, and the flowers will wilt. If the flowers are not watered for a long time, the older leaves and the leaves at the bottom of the plant will gradually turn yellow and dry up. If most grass flowers are in a state of drought for a long time, the plants will be short, the leaves will lose their bright green luster, and even the whole plant will die. Some flower growers are afraid of excessive watering, so they water "half waist water" every time, that is, the amount of water poured can only moisten the topsoil, while the lower soil is dry. This watering method will also affect the development of the root system of flowers and cause the above-mentioned undesirable phenomena. Therefore, watering should be done when the soil is dry and wet, and water thoroughly when watering.

　　11. How to judge whether potted flowers are short of water?
　　Watering is a regular management work for flower cultivation. Whether the pot soil is short of water is a difficult thing to grasp, so many flower lovers often feel distressed about this. The following is a brief introduction to the experience of flower growers in judging whether there is a lack of water. (1) Tapping method. Use the joints of your fingers to gently tap the upper middle wall of the flower pot. If a relatively crisp sound is heard, it means that the soil in the pot is dry and needs to be watered immediately; if a dull sound is heard, it means that the soil in the pot is moist and you can temporarily stop watering. (2) Visual inspection method. Use your eyes to observe whether the color of the surface of the pot soil changes. If the color becomes lighter or grayish white, it means that the soil in the pot is dry and needs to be watered; if the color becomes darker or brown, it means that the soil in the pot is moist and you can temporarily stop watering. (3) Finger measurement method. Gently insert your finger into the soil about 2 cm deep and touch the soil. If it feels dry or rough and hard, it means that the soil in the pot is dry and needs to be watered immediately; if it feels slightly moist, delicate and soft, it means that the soil in the pot is moist and you can temporarily stop watering. (4) Pinching and twisting method. Use your fingers to twist the soil in the pot. If the soil is powdery, it means that the soil is dry and you should water it immediately. If it is flaky or granular, it means that the soil is moist and you don't need to water it for the time being. The above test methods are all based on experience. They can only tell people the approximate dryness and wetness of the pot soil. If you need to know the exact dryness and wetness of the pot soil, you can buy a soil thermometer, insert the thermometer into the seal, and you can see the words "dry" or "moist" on the scale, so you can know exactly when to water.

　　12. Why is it not appropriate to use cold water to water flowers at noon in midsummer?
　　At noon in midsummer, the temperature is very high, and the temperature of the leaves of flowers can often reach about 40℃. The transpiration is strong, and the water evaporates quickly. The root system needs to continuously absorb water to replenish the loss of transpiration from the leaves. If you water with cold water at this time, although water is added to the pot soil, the root hairs will be stimulated by the low temperature due to the sudden drop in soil temperature, which will immediately hinder the normal absorption of water. At this time, since the flowers have no preparations in their bodies, the stomata on the leaves are not closed, and the water supply and demand balance is lost, causing the leaves to wilt from a tense state, causing the plants to produce "physiological drought", the leaves to scorch, and in severe cases, the whole plant will die. This phenomenon is particularly obvious in herbaceous flowers, such as geraniums, morning glory, and aster, which are most afraid of being watered with cold water at noon in hot weather. For this reason, it is best to water flowers in the morning and evening in summer.

　　13. What kind of water is good for watering flowers?
　　Water can be divided into hard water and soft water according to the salt content. Hard water contains more salts. Using it to water flowers often causes brown spots on the leaves of flowers, affecting the ornamental effect. Therefore, soft water is suitable for watering flowers. Among soft waters, rainwater (or snow water) is the most ideal, because rainwater is a kind of water that is close to neutral, does not contain minerals, and has more air, which is very suitable for watering flowers. If rainwater can be collected and stored on rainy days for watering flowers, it will help promote the assimilation of flowers, extend the cultivation period, and improve the ornamental value. Flowers that like acidic soil prefer rainwater. Therefore, more rainwater should be stored during the rainy season. In various parts of Northeast China, snow water can be used to water flowers, and the effect is also very good, but attention should be paid to It is necessary to melt the ice and snow and leave it until the water temperature is close to room temperature before use. If there is no rain or snow water, river water or pond water can be used. If tap water is used, it must be stored in a bucket (tank) for 1-2 days to allow the chlorine in the water to evaporate before use, which is safer. Do not use laundry water containing soap or washing powder for watering flowers, nor dishwashing water containing oil. For cactus flowers that like slightly alkaline, it is not appropriate to use slightly acidic leftover tea water. In addition, you should also pay attention to the temperature of the water when watering flowers. Whether it is summer or winter watering, the water temperature is too different from the air temperature (more than 5 degrees) and it is easy to damage the roots of flowers. Therefore, it is best to put the water for watering flowers in a bucket (tank) and dry it for a day, and then use it when the water temperature is close to the air temperature.

　　14. How should the amount of water for potted flowers be controlled?
　　Whether the amount of watering for potted flowers can be timely and appropriate is the key to the success of flower cultivation. Based on the experience of various places, the amount of watering for potted flowers is determined by comprehensive judgment based on the flower variety, plant size, growth and development period, climate, soil conditions, flower pot size, placement location and other aspects to determine the time, frequency and amount of watering. Under normal circumstances, moisture-loving flowers should be watered more, and drought-loving flowers should be watered less; bulbous flowers should not be watered too much; herbaceous flowers have a large water content and a large transpiration rate, so they need more water than woody flowers; flowers with large and soft leaves, smooth and hairless should be watered more, and flowers with small leaves with waxy layers, hairs and leather should be watered less; more watering during the vigorous growth period and less watering during the dormant period; more watering for large seedlings and small pots, less watering for small seedlings and large pots; more watering on hot days and less watering on cold days; more watering on dry days and less watering on cloudy days. For general flowers, the water supply in the four seasons is: the temperature gradually rises after the beginning of spring every year, and the flowers enter the vigorous growth period, and the amount of watering is gradually increased. Watering in early spring should be done before noon. In summer, the temperature is high, the flowers grow vigorously, and the transpiration is strong, so the amount of watering should be sufficient. Watering in summer should be done in the morning and evening. After the beginning of autumn, the temperature gradually drops, the flowers grow slowly, and watering should be reduced appropriately. In winter, the temperature is low, and many flowers enter a dormant or semi-dormant period. Watering should be controlled. Do not water if the pot soil is not too dry, so as to avoid root rot and leaf fall due to excessive watering. Watering in winter should be done at 1-2 pm.

　　15. What is the role of spraying water?
　　Spraying water can increase air humidity, lower the temperature, wash away dust on the plants and flush away pests, etc., avoid scorching of tender leaves and early withering of flowers, and keep plants fresh; especially some flowers that like shade and humidity, such as camellia, azalea, orchid, monstera, etc., often spraying water on the leaves is very beneficial to their growth and development. In summer, when it is sunny after rain or hot at night, you should pay attention to spraying water to cool down and prevent diseases. The amount of water sprayed should be determined according to the needs of flowers. Generally, the water can evaporate soon after spraying water, and this amount of water spray is most suitable. Seedlings and delicate flowers need to be sprayed with water more often. Newly potted and unrooted cuttings also need to be sprayed with water more often. Tropical orchids, Araceae and Bromeliaceae flowers need to be sprayed with water more often. However, some flowers are very sensitive to water and humidity, such as Gloxinia, Calceolaria, Begonia, etc., whose leaves have thick hairs. After water falls on them, it is not easy to evaporate and cause the leaves to rot. Therefore, it is not advisable to spray water on the leaves. For blooming flowers, it is also not advisable to spray water too much, otherwise it is easy to cause the petals to rot or affect fertilization, and reduce the fruiting rate. In addition, the leaf buds at the top of the cyclamen tuber, the flower buds in the gerbera leaf cluster, and the pseudobulb in the center of the Clivia leaf cluster are all afraid of water and humidity. These parts are easily harmed after spraying water.

　　16. How to save flowers after they wilt?
　　Potted flowers, because there is less water in the pot, forget to water, especially in the hot summer, often cause the leaves to wilt. If they are not saved in time, they will often cause the plants to wither. If the rescue is not done properly, it may sometimes cause the death of the plant. The correct approach is: when the leaves are found to be wilting, the flower pot should be moved to a cool place immediately, some water should be sprayed on the leaves, and a small amount of water should be poured. Later, as the stems and leaves gradually recover, the amount of watering should be gradually increased. If too much water is poured at this time, it may cause the death of the plant. This is because a large number of root hairs are damaged after the flowers wilt, so the water absorption capacity is greatly reduced. Only after the new root hairs are grown can the original water absorption capacity be restored. At the same time, wilting causes the cells to lose water. After encountering water, the cell wall absorbs water first and expands rapidly, and the protoplasm absorbs water later, and the expansion speed is slow. If a large amount of water is poured suddenly at this time, it will cause the separation of the cell wall and damage the protoplasm, thus causing the death of the flowers.

　　17. What role does soil play in the growth and development of flowers?
　　Soil is an important matrix for cultivating flowers, the material basis for the survival of flowers, and the main source of water, fertilizer, air, and heat required for the growth and development of flowers. This is because soil is composed of minerals, organic matter, soil moisture, and soil air. Minerals are the most basic substances that make up the soil, and they can provide a variety of nutrients required by flowers. Organic matter not only supplies nutrients for the growth of flowers, but also plays an important role in improving the physical and chemical properties of the soil and the structure of soil aggregates, as well as water retention, water supply, ventilation, and temperature stability. Soil moisture is an indispensable material condition for the growth of flowers. Soil air is the source of oxygen required for the absorption of flower roots and the life activities of microorganisms, and is also an important condition for the further weathering of soil minerals and the conversion of organic matter to release nutrients. Scientific experiments have shown that the soil suitable for plant growth, by volume, contains about 38% minerals, about 12% organic matter, and about 15%-35% soil air and soil moisture. According to some information, the most suitable water content for the growth of general flower plants is 25% of the soil volume, and air also accounts for 25%. Some people do not understand the above principles. When cultivating potted flowers, they do not change the pots and soil for a long time, which causes the physical and chemical properties of the soil to deteriorate, the ventilation and water permeability are poor, and the nutrients are lacking, which leads to poor growth of flowers, yellow leaves, less flowering, or even no flowering. Therefore, to grow potted flowers well, you must pay attention to changing pots and soil in time.

　　18. What kind of soil is good for potted flowers?
　　Potted flowers, because their roots can only move in a very small range of soil, have stricter requirements on soil than open-field flowers. On the one hand, it requires nutrients to be as comprehensive as possible, and the nutrients needed for the growth of flowers in the limited pot soil; on the other hand, it requires good physical and chemical properties, that is, the structure should be loose, the water holding capacity should be strong, the pH should be appropriate, and the fertilizer retention should be good. It is for this reason that when growing flowers, you should try to choose a neutral or slightly acidic soil with a good aggregate structure, loose and fertile, good water retention and drainage performance, and rich in humus. This kind of soil is light in weight, large in pores, airy, and rich in nutrients, which is conducive to the development of the root system of flowers and the healthy growth of plants. If flowers are planted in heavy clay soil with poor ventilation and water permeability, or in pure sandy soil that lacks nutrients and has poor water and fertilizer retention, or in alkaline soil, most flowers will easily grow weak or even die. However, the soil conditions mentioned above are not available in any natural soil. Therefore, artificial culture soil should be used for potted flowers. This culture soil is made by mixing two or more soils or other matrix materials in a certain proportion according to the different growth habits of flowers and plants to meet the needs of different flowers.

　　19. How to prepare culture soil?
　　There are many materials suitable for preparing culture soil. The following are commonly used. (1) Plain sandy soil. Mostly taken from river beaches. It has good drainage performance but no fertility. It is often mixed with other culture materials to facilitate drainage. (2) Garden soil. Soil taken from the surface layer of vegetable gardens, orchards, etc. It contains a certain amount of humus and has good physical properties. It is often used as the basic material for most culture soils. (3) Leaf mold. Made from fallen leaves, dead grass, etc. It has a high humus content, strong water retention, and good permeability. It is one of the main materials for preparing culture soil. (4) Mountain mud. It is divided into black mountain mud and yellow mountain mud. It is formed by the long-term accumulation of fallen leaves from trees in the mountains. Black mountain mud is acidic and contains more humus; Huangshan mud is also acidic and contains less humus. (5) Peat soil. It is formed by the carbonization of peat moss. Due to the different stages of formation, it is divided into brown peat and black peat. Brown peat contains rich organic matter and has an acidic reaction; black peat contains more minerals and less organic matter, and has a slightly acidic or neutral reaction. (6) Rice husk ash. It is the ash formed by burning rice husks. It is slightly alkaline, contains potassium, and has good drainage and air permeability. (7) Manure soil. It is made by mixing animal feces, fallen leaves, etc. with garden soil, sewage, etc. and piling them up and fermenting. It has rich fertility. In addition, pond mud, river mud, coniferous soil, turf soil, rotten wood chips, vermiculite, perlite, etc. are all good materials for preparing culture soil. The preparation of culture soil should be flexibly mastered according to the growth habits of flowers, the properties of the culture soil materials and local conditions. For general potted flowers, the commonly used culture soil configuration ratio is leaf humus (or peat soil): garden soil: river sand: bone meal = 35:30:30:5, or leaf humus (or peat soil), plain sandy soil, decomposed organic fertilizer, superphosphate, etc. are mixed and sieved at 5:3.5:1:0.5. The above culture soils are mostly neutral or slightly acidic, which are suitable for most flowers. For cultivating acid-loving flowers and trees such as camellia and azalea, about 0.2% sulfur powder can be added; for cultivating flowers such as cacti, about 10% of the wall skin soil peeled off from the lime wall can be added.

　　20. How to make leaf humus by yourself?
　　Leaf humus is a commonly used material for cultivating potted flowers. Where conditions permit. You can go to the forest in the mountains and directly dig up the leaf humus that has been weathered for many years. You can also make your own leaf humus. The method is: collect fallen leaves, weeds and other things from broad-leaved or coniferous trees in autumn and pile them into a rectangular pit. When piling, put a layer of leaves first, then a layer of garden soil, and pile them up several layers repeatedly, then irrigate with a small amount of sewage, and finally cover the top with a layer of garden soil and other things about 10 cm thick. Open it once in late spring and midsummer of the next year, turn over and crush the pile, and then pile it up as it was. In warm climate areas, these piles can mostly be decomposed by late autumn. At this time, they can be dug out, further crushed and sieved for use. Two points should be noted when piling: First, do not press too tightly to facilitate air penetration, create conditions for the activity of aerobic bacteria, and thus accelerate the decomposition of the pile. Second, do not make the pile too wet. If it is too wet, the ventilation will be poor. Under anaerobic conditions, anaerobic bacteria will multiply and move in large numbers, causing serious nutrient loss and affecting the quality of the leaf humus.

　　21. How to determine and change the pH value of the culture soil?
　　The pH value of the culture soil directly affects the physical and chemical properties of the culture soil and the growth of flowers. Most flowers grow well in culture soil with a neutral to slightly acidic pH value (pH value 5.5-7.0). Because within this range, the nutrients absorbed by flowers from the soil are in a soluble state. Above or below this limit, some nutrients become inabsorbable, which can easily cause nutritional deficiencies in some flowers. It is for this reason that the pH value of the culture soil needs to be determined before planting flowers. The pH value of the soil is usually expressed in pH. A pH value of 7 is neutral, less than 7 is acidic, and greater than 7 is alkaline. If the soil is too acidic or too alkaline, it needs to be improved in order to grow flowers well. The easiest way to determine the pH value of the culture soil is to go to a chemical reagent store and buy a box of litmus paper, which contains a pair of standard colorimetric plates. Determination: Put a small amount of culture soil in a clean glass cup, add cold boiled water in a ratio of 1:2, stir and settle, put litmus paper into the solution, take out the test paper and compare it with the standard color plate for about 1 or 2 seconds, and find the color plate number with a similar color, which is the pH value of this culture soil. According to the test results, the following measures can be taken to adjust the culture soil with inappropriate pH. If the acidity is too high, add a small amount of lime powder to the potting soil; if the alkalinity is too high, add a small amount of sulfur powder to the potting soil.