How should the leaves of zinnia turn yellow? control watering and properly loosen the soil / spray with medicine in case of diseases and insect pests.

Zinnia, a highly ornamental plant, has a long flowering period and rich colors, and is potted at home by many flower friends. However, in the process of raising zinnia, many novices will encounter the situation of yellow leaves, thus affecting the ornamental, then how to do the yellowing of the leaves? In this regard, the editor summed up the reasons for the yellowing of the leaves of four kinds of zinnia. Flower friends with problems come in and have a look!

One, how does the hundred-day grass leaves turn yellow? find the cause.

In daily life, there are many people who raise zinnia, but there may be more beginners, and many of them do not follow the method of raising zinnia, so there are often all kinds of problems, including yellowing of leaves. As for the yellowing of the leaves of zinnia, the editor summed up four points and attached a solution. Let's move on.

2. the causes of yellowing of the leaves of zinnia and its solutions

1. Environmental mutation

In fact, there are many reasons for the yellowing of the leaves of zinnia, but we should first consider environmental factors. The reason for this is that many flower friends buy their hundred-day grass online, which may have a large geographical span, and the hundred-day grass can not adapt for a while, resulting in leaf yellow symptoms.

Solution: at this time, you can communicate with the shop owner to understand the growth environment before the hundred-day grass purchase, and then we create the same environment at home, and then slowly change until the plant fully adapts to the current environment. After a period of time, the hundred-day grass will return to health.

2. Too much watering

Hundred-day grass is not afraid of strong light, and needs sufficient light, so the water loss is very fast, and we need to water regularly. However, many flower friends tend to water too much, resulting in stagnant water in the basin soil, resulting in root rot, resulting in symptoms of yellow leaves.

Solution: what if the leaves of Zinnia turn yellow? At this time, we should move the pot to the ventilated sun, let the water evaporate quickly, or simply change the pot soil directly. In daily maintenance, we had better keep the soil dry after watering, so as not to dry and water in order to avoid the emergence of yellow leaves.

3. Soil consolidation

Zinnia has a high demand for water. If the soil is hardened, the water can not penetrate into the soil layer, resulting in the plant roots can not absorb water and nutrients. However, when the leaves are filled with water and nutrients, there will naturally be symptoms of leaf yellowing.

Solution: at this point, we need to loosen the soil. Specific approach: use loosening tools to insert the basin soil into the basin edge, gently shake the basin soil to make the basin soil have a sense of crack on the line. Then we pour proper water, and after a period of time, the leaves can recover.

4. Diseases and insect pests

In addition to the above points, some diseases and insect pests are also easy to cause leaf curl. At this time, we can observe the leaves, if it is caused by pests can use insecticides to kill insects, if it is caused by bacteria can be treated with antibiotics. As for what kind of medicine to use, there is a detailed introduction in the pest control of Zinnia, so I won't say much here.

How to raise hundred-day grass, the breeding methods and matters needing attention / heart-picking are very important.

Zinnia, a very beautiful herb, has a long flowering period, rich flowers and colors, and is easy to feed, so it is welcomed and loved by the majority of flower friends. In life, many flower friends will plant zinnia at home, but many of them do not know how to raise it. In this regard, the editor carefully sorted out the breeding methods and matters needing attention of zinnia, which is very comprehensive. Friends who want to raise must have a look at it.

First, how to raise the hundred-day grass and understand the habits

Indoor farming is not like the wild, everything needs to be created by ourselves, so how to raise zinnia, we need to create the best growth environment according to its growth habits. In this regard, the editor will bring you the breeding methods and matters needing attention from the aspects of soil, light, temperature, moisture, fertilization, pruning and so on. Let's move on.

2. Culture methods and matters needing attention of zinnia

1. Soil

How to raise potted zinzinnia, the first thing is to choose the soil. Because the zinnia has strong vitality and good adaptability, the demand for soil is not high. But if you want to raise the hundred-day grass well, it is best to choose the soil made of rotten leaf soil, perlite and river soil. Of course, ordinary soil can also be used, and fertilizing in the later stage is fine.

Note: the hundred-day grass likes the humid environment and requires us to water frequently, so the soil should be loose and well drained, otherwise it is easy to accumulate water, or it is difficult to absorb water from the roots, resulting in poor plant growth.

2. Lighting

In the cultivation method of zinnia, light is indispensable, but we don't have to worry about it at all, because zinnia can be directly exposed to the sun, just basking in the sun all day. Of course, the worry is that you don't need shade, and it's necessary to keep it full of light.

Note: the hundred-day grass needs enough light. If you find that the leaves of the plant are spaced apart, it means that the light is not enough and there is a phenomenon of overgrowth. At this time, we should add light to the hundred-day grass.

3. Temperature

It is understood that the hundred-day grass likes to be warm and sunny, and cannot bear the heat, high temperature and cold, so we must pay attention to adjust the temperature at any time in the process of raising the hundred-day grass.

Note: if we want to raise hundred-day grass well, we need to control the temperature. Keep the temperature at 18-20 ℃ during the day and 15-16 ℃ at night. It is worth mentioning that zinnia grows very rapidly in summer.

4. Watering

How to raise zinnia, watering is very important. Because the hundred-day grass needs sufficient light, and is not afraid of strong light, under this condition, the water in the basin soil will lose very quickly, so we need to water it often. If it is summer, we can water the hundred-day grass every day.

Note: hundred-day grass needs a lot of water, so watering can not be too little, but not too much, otherwise it is easy to affect plant growth, resulting in the emergence of yellowing leaves. As for how to control the amount of watering, there is a detailed introduction in the watering method of zinnia, so I won't say much here.

5. Fertilization

After watering, let's talk about fertilization. If we plant a hundred-day grass in a pot at home, we need to fertilize it timely, usually once a month and a half. As for fertilizer, you can choose compound fertilizer.

Note: when applying fertilizer, first melt the fertilizer with an appropriate amount of water, and then pour it into the basin soil to avoid excessive concentration of fertilizer, resulting in rotting roots. In addition, when applying fertilizer, avoid the leaves and prevent them from burning out.

Third, matters needing attention in the culture of zinnia

Although there are a lot of points for attention in the breeding methods of zinnia above, there are still many things that flower friends need to pay attention to if they want to raise it well. To put it simply, there are two points for attention in the cultivation of zinnia:

1. Trim-pick the heart

In the breeding process of zinnia, there is one thing we must pay attention to, that is, picking the heart, because if the grass is not plucked, it will cause the symptom of few flowers. As for how to pick the heart of the hundred-day grass, there is a detailed introduction, so I won't say much here.

2. Diseases and insect pests

If you plant zinnia indoors, it will inevitably be disturbed by diseases and insect pests. It is understood that the common diseases of zinnia are white star disease, black spot disease, mosaic disease, these diseases all appear on the leaves, seriously affecting the ornamental of the plant. Therefore, when diseases and insect pests are found, they should be sprayed immediately. As for what kind of medicine should be sprayed, there is a detailed introduction in the pest control of Zinnia, so I won't say much here.

Dahlia, also known as Dahlia, Tianzhu peony, peony, sweet potato flower, marble, passionflower and chrysanthemum, is a perennial herb of Compositae. The colors of dahlias are colorful, with red, yellow, orange, purple, white and other colors, very attractive. Dahlia adapts to different climates and soils throughout the country, with few diseases and insect pests, easy to manage and best to breed. However, it is often harmed by the following diseases and insect pests: spots occur after the symptoms of Dahlia mosaic disease, brown and green along both sides of the veins, translucent "bright veins", yellowish patches appear on the diseased leaves, leaves wrinkle, growth stagnant, and plants are short. Plants grown from infected roots rarely grow to normal height. The pathogen Dahlia mosaic virus (Dahlia Mosaic Virus), which is icosahedral, is transmitted by aphids and Ye Chan. It can also be transmitted by grafting. The virus can also infect zinnia, snake chrysanthemum, golden chicken chrysanthemum and petunia. In addition, cucumber mosaic virus (CMV), tobacco necrosis virus (TSV) and tomato spot wilt virus (TSWV) can also cause virus disease in Dahlia. Control methods 1. Root tubers or sprouting buds of diseased plants should not be used as culture materials. 2. Observe carefully and remove the diseased plant and burn it in time. 3. Spray 50% malathion 1000 times or 40% dimethoate 1500 times and 25% carbaryl 800 times to control virus-borne pests. Symptoms of Botrytis cinerea disease in Dahlia the flowers are easy to be damaged and turn brown, and then soft rot occurs. In severe cases, the buds can not open, resulting in gray mildew (pathogen fruiting body). Therefore, gray mold is also known as flower rot. When the disease occurs on the leaves, there are nearly round to irregular disease spots, which often occur at the edge of the leaves, light brown to brown, sometimes showing wheel patterns, watery, and gray mold when the humidity is high. The stem spot is brown, sometimes showing a wheel pattern, watery, and gray mold grows when the humidity is high. The disease spot on the stem is brown and irregular, and the stem softens and collapses when it is serious, which is the main disease of Dahlia. The pathogen Botrytis cinerea [Botrytis cinerea Pers.] belongs to the subphylum Botrytis cinerea. The conidiophores are slender, branched, sometimes bifurcate near the top, and there are single cells of conidia on the short peduncles, ovoid, usually producing black, irregular sclerotia. The pathogen of transmission overwintered mainly by sclerotia along with the residue of the diseased plant. Under suitable conditions, sclerotia grow conidiophores, produce conidia, and cause secondary infection. The conidiophores produced on the disease spot produce conidia and cause primary infection. The conidia produced on the disease spot are transmitted by wind and rain, causing re-infection. The harm is serious in rainy season, and the host range of pathogen is wide. Prevention and control methods 1. Because Botrytis cinerea is parasitic and saprophytic, diseased flowers and leaves should be cut off and buried in time. 2. Implement rotational planting. Or switch to germ-free new soil. 3. Strengthen cultivation management to avoid planting too dense, so as to facilitate ventilation and light transmission. Do not sprinkle the plant when watering, so as not to spread germs by splashing. Pay attention to the elimination of stagnant water after rain. Dahlia powdery mildew symptoms Dahlia powdery mildew harms leaves, buds, flower stalks and flower buds. There is a layer of white powder on the surface of the disease, that is, conidia. Several small disease spots on the leaves can be connected to form large disease spots. After being killed, the plant is short, the leaf surface is uneven or curly, and the tender shoot is malformed. Flower buds cannot blossom or only produce deformed flowers after being killed. In severe cases, it can dry up the leaves and even kill the whole plant. Autumn and winter produce gray mycelium and a few small black spots. The small black spot is a closed capsule. The pathogens are Polygonum powdery mildew Erysiphe polygoni DC., ascomycetes and powdery mildew. The hyphae grow on the positive and negative sides of the leaves. The route of infection overwintered by mycelium. When the temperature rose to 18 ℃-25 ℃ in the next year, the mycelium began to grow and produced a large number of conidia. When the environmental conditions were suitable, the mycelium germinated and grew, producing sucking cells and absorbing nutrients in the tissue. High temperature and humidity are conducive to the disease. Prevention and control methods 1. Cut off and destroy the diseased plants. 2. During the disease season, the symptom root and tuber root of Dahlia bacterial wilt were browned and rotted by spraying with 1500 times solution of 15% Fenrugin wettable powder or 70% methyl thiophanate wettable powder or 50% carbendazim wettable powder, and the aboveground leaves wilted and drooped. Cross-section of the diseased root, stem, xylem was yellowish brown, and bacterial pus overflowed. The pathogen is bacterial wilt pathogen Pseudomons solanacearum E.F.smith. The pathogens of infection can saprophyte in the remains of diseased plants or in the soil, and breed in large quantities in the environment of high temperature and high humidity, and invade from the wound when the host is encountered. When transplanting in high temperature and rainy season, if the soil or fertilizer carries Ralstonia solanacearum, the disease is most likely to occur. Prevention and control methods 1. Cultivate disease-free seedlings and avoid selecting breeding materials in disease areas. 2. Do not plant in the soil where the disease has occurred. Strengthen the management of seedlings to avoid wounds. Watering should be appropriate, and irrigation water in the disease area should be prevented from flowing to healthy plants. Diseased plants should be removed and burned. 3. Improve the soil: spread 100-150 kg of hydrated lime per mu, apply enough rotten farm manure, turn over the soil, make the soil fertile, loose and slightly alkaline, so as to inhibit the reproduction of bacteria and enhance plant resistance. 4. Chemical prevention and control: 1) remove and burn the diseased plants in time, inject 2% formaldehyde solution or 20% lime water into each hole for disinfection, or sprinkle lime powder. 2) at the initial stage of the disease, streptomycin was sprayed with 4000 times of streptomycin or 30%DT (copper succinate) wettable powder, 70%DTM wettable powder was sprayed, or 77% of the solution was killed. Spray every 7-10 days, 3-4 times in a row. 3) the above agents can also be used to irrigate the roots, 0.5 kg per plant, combined with spray, once in 7-8 days, 3-4 times in a row. Dahlia dark streak symptoms of the leaf surface and leaf edge of the round or semicircular dark green wheel-like disease spot. The spot turns dark brown and grayish green in the middle. There are black spots and small particles on the surface of the lesion. When seriously ill, the leaves wither and droop. Pathogen Phyllosticta dahliaecola Brunaud. It is called Dahlia Flower and Leaf spot Fungi, which belongs to the subphylum Dahlia. Through the route of transmission, the conidia stayed on the surface with the diseased remains to survive the winter. After the conidia germinated in the following year, the budding tube invaded the host. After that, conidia and conidia were produced in the disease department, which spread by wind and rain and re-infected. The temperature of 21 ℃ is favorable for its occurrence or epidemic. Prevention and control methods 1. After harvest, thoroughly remove the disease and debris and concentrate on burning or turning over the land, so as to reduce the source of primary infection. 2. At the initial stage of the disease, 75% chlorothalonil wettable powder 500x, 40% polysulfide suspension 500x, 50% mixed sulfur suspension 500x, 1 200 Bordeaux, 77% Kill wettable powder 500x, 50% copper succinate (DT) wettable powder 400,500x, once or twice every 10 days were sprayed. Dahlia flower blight symptoms Corolla disease. The top part of the petal is light brown, with round or subcircular spots, then the petals expand, the petals wither from the disease, and gradually turn brown and die. The lateral Corolla develops to the medial Corolla, resulting in rotten petals sagging. The conditional pathogens could grow at 5-25 ℃, and 20-25 ℃ was the most suitable. It is rainy in autumn and the double large flowers are seriously ill. The pathogen Itersonilia perplexans Derx belongs to fungal semi-knowing subphylum, Trichoderma, Lepidoptera, Pseudomonas fungal. The hyphae of the bacteria are easy to form a lock-like union, and some cells of the hyphae form small stalks, which produce asymmetrical colorless spores and emit powerfully. The bacteria living on the remains of diseased flowers are the source of infection of the disease. The control method can refer to the chrysanthemum black spot. Wet rot occurred at the base of the plant with symptoms of white silk disease of Dahlia, which was brown and black at first, then produced white silk mycelium and formed sclerotia the size of rapeseed. The pathogen of Sclerotinia sclerotiorum [Sclerotium rolfsii Sacc.] belongs to the subphylum of half-known bacteria. The hyphae are white, loose or agglomerated into a linear shape and attached to the substrate, forming a sclerotia, which is small (0.5-1.0 mm in diameter) and neat, initially white, then yellowish brown, and then grayish white inside. The pathogen of transmission survived in the soil and plant residues for many years with mycelium and sclerotia, and invaded the host from the root neck of the plant. The pathogen has a wide range of hosts, such as Iris, orchid, peony, pyrethrum, peach, pear and so on, causing quenching, root rot, base rot and fruit rot. Control method 1, pull out the diseased plant, burn the sclerotia in the soil, spread lime in the disease point, or fill it with poisonous soil made of 70% pentachloronitrobenzene powder and 100 times new soil for disinfection. 2. At the initial stage of the disease, the stem base of the diseased plant was irrigated with 50% topiramate wettable powder 500 times or 50% carbendazim wettable powder 500 times, and irrigated again every 7-10 days. Willow bat moth, also known as oriental bat moth, belongs to Lepidoptera, Batmoth family. Distribution and damage are distributed in Heilongjiang, Jilin, Liaoning, the former Soviet Union, Japan and other places. Do harm to many kinds of flowers and trees. For harmful larvae to damage branches and stems, the entrance of the road is often sunken and annular, and the screen is covered with sawdust to form a sawdust package. Morphological characteristics adult body length 35-44 mm, wingspan 66-70 mm. Body pink brown to tea brown. Antennae short linear. The front edge of the forewing is ringed with a dark greenish, angular stripe in the center, and two broad brown diagonal bands on the outer edge of the stripe. The hind wings are narrow and the abdomen grows. Ovoid, 0.6-0.7 mm in diam., black, slightly glossy. The larvae are dark brown, dirty white in chest and abdomen, cylindrical in shape, with yellowish-brown tubercles on the body, and the length of the mature larvae is 44-57 mm. Most of the life history habits in Liaoning Province are 1 generation in 1 year and 1 generation in 2 years, overwintering with eggs on the ground or larvae at the base. The next spring began to hatch in the middle of May. In early June, it turned to fruit growers, trees or weeds and other stem food damage. Pupation begins in early August and ends in late September. Eclosion into adults in late August. The peak period of Eclosion is in mid-September and finally in mid-October. Adults mate and lay eggs after Eclosion. Overwintering with eggs. Part of the larvae hatched in the later stage, or those whose growth is delayed by other interference, overwintered as larvae. In the following year, it began to Eclosion into adults in July, and then spawned for two years to complete one generation. Most of the adults emerged from 16 to 18:00. Adults often hang from tree trunks, trees or weeds during the day and do not begin to fly, mate or lay eggs until after sunset. Adults are backlit. Spawning immediately after mating, there is no certain place to lay eggs, most of them lay eggs one by one with the trembling of their wings, some lay eggs at the end of the mating, and most of them lay eggs without mating. The number of eggs laid by females ranges from hundreds to thousands. Prevention and control methods 1. Cut off the seedlings and branches with sawdust bags. 2. Chemical control: 1000 times parathion solution was sprayed to the ground when the early instar larvae were active on the ground from late May to early June. When the middle-aged larvae transfer to the trunk, drop 50% dichlorvos 10 times into the wormhole. Short-forehead negative locust, commonly known as grasshopper, is widely distributed. the harmful flowers are impatiens, cockscomb, a string of red, pansy, goldfish grass, thousand-day red, calendula, hundred-day grass, daisy, chrysanthemum, echinacea, rose, jasmine, mulberry, dahlia, gardenia and so on. For the injurious early instar nymphs like to eat the damaged leaves, the injured leaves show a network, and then disperse feeding later, resulting in leaf gaps and holes, leaving only the main vein of the whole leaf in severe cases. The adult is 21-31 mm long and is light green to brown and yellowish. The head protrudes forward. The hind foot is developed as a jumping foot. Front wings are green. The rear wing is red at the base and green at the end. There is a yellowish-brown secretion outside the egg mass. Single egg milky white, oval. The nymph is light green at first, with white spots on the cloth, resembling an adult, wingless and only with wing buds. The life history and habits of the insect occur two generations a year in the Yangtze River Basin and other areas. Overwintering with eggs in the soil. From May to June of the following year, the eggs hatched. In early July, the first generation of adults began to lay eggs. The middle and last ten days of July are the peak spawning period. The second generation nymphs began to hatch in late July, and the hatching peak was in the first and middle of August. From mid-late September to early October, the second generation adults began to lay eggs, and the peak spawning period was from late October to early November. Control methods: 1. When the nymphs of the first instar are concentrated, they should be killed manually. 2. Spray 50% fenitrothion emulsion 1000 times, or 25% imidophos 1000 times.