What s going on with watermelon leaves starting to turn yellow and wither? The old leaves are yellow

Watermelon leaves begin to turn yellow and wither, which cannot simply be thought of as caused by drought and lack of water or too much water, there are two possibilities.

1. Improper fertilization.

1. The farm manure is applied to the field, but it is not rotten or there is too much chemical fertilizer, and there is a phenomenon of burning roots.

2. Foliar fertilizer is sprayed too much, and some foliar fertilizers contain hormones, which will poison watermelon, and the leaves of watermelon will be yellow, rigid and deformed. Like Zenfat amino acids.

Foliar fertilizer, which is very safe, will not be the case.

Prevention method: Farmhouse manure can only go up to the ground after it has been decomposed. If you apply chemical fertilizer in the field, do not simply apply nitrogen fertilizer, but should also apply some phosphorus fertilizer and potassium fertilizer. Nitrogen fertilizer can not be too much, and if there is too much nitrogen fertilizer, it is normal for root burning to occur.

If there is already burning roots in the ground, some microbial agents should be applied in the ground, and about 20 catties per mu of land is about the same. If you plant watermelons in the greenhouse, there is a phenomenon of burning roots, in addition to flushing and applying pesticides, it is necessary to break the membrane and ventilate.

2. Caused by drug damage.

Watermelons are generally treated with post-emergence herbicides.

Weeding. When transplanting, pay attention to the order. Generally, ridges are leveled, herbicides are sprayed, and holes are dug when planting. When planting, the layer of soil with herbicides can be lifted to prevent damage to the roots of the watermelon.

However, in the north, it is a small arch model, and it is generally used with double membranes. Some growers are dual-purpose, arching the film in the early stage, and covering the film in the later stage, which will cause pesticide damage and cause the watermelon leaves to turn yellow.

Prevention method: To let the wind blow, many will use microbial agents to irrigate the roots, and then water, which can alleviate this phenomenon.

3. Lack of nutrients. Many people grow watermelons, often in succession.

In this way, it is very easy to cause the phenomenon of nutrient deficiency. If the watermelon is deficient in potassium.

Calcium deficiency and boron deficiency, watermelons will have yellow leaves.

Prevention: Do not crop continuously.

If continuous cropping, watermelons that have been deficient in nutrients should be supplemented with mineral fertilizers in addition to the main fertilizer. Spray some foliar fertilizer. Replenish nutrients in a timely manner.

Fourth, caused by soil salinity.

Generally, when planting watermelons in greenhouses, it is easy to have salt damage, mainly because there is more chemical fertilizer or some chicken and duck manure for a long time. Watermelons planted in such soil are prone to yellow leaves.

If it is planted in the open field, it is more likely to occur in continuous cropping land.

Prevention: Preferably crop rotation. Chicken manure and cow manure should not be too much. If the soil is damaged by salt, it is generally slightly improved with microbial agents.

Watermelon seedlings are not tolerant to exposure to the sun, and if the light is too strong, it will appear yellow. The growth of watermelon seedlings needs sufficient water, and the plants will also appear yellow if they lack water, and the temperature is too low or too high to cause the watermelon seedlings to turn yellow, and it may be caused by applying thick fertilizer or excessive fertilization.

The leaves of the watermelon are yellow and withered from the beginning of the roots before they are ripe, which is caused by physiological diseases. The main reason is the improper use of fertilizer and water and the formation of management reasons. This situation is generally presented in the greenhouse planting in the maintenance area, and the outdoor planting is rarely presented.

Watermelons need sandy soil with good water permeability and air permeability, and prefer a sunny, warm, and dry environment. But now the greenhouse is planted all year round, and the artificial conditions are changed to make it grow, so that there will be a variety of new pests and diseases and bad conditions, but even if it is so, it must be fundamentally followed by its normal growth habits, only in this way can the harvest be better!

1.Management Elements:

Most of the watermelons planted in greenhouses are planted in the opposite season, the early spring planting is more, the weather is still very cold when planting, the melon farmers are covered with grass curtains in order to keep warm, and the grass curtain is covered with grass curtains, and the light time is reduced, the night time is lengthened, the temperature difference between day and night is very small, and the respiration consumes too much and the plants grow.

2.Water Control Elements:

In order to make it grow as quickly as possible, the roots are all in the shallow soil layer and do not have deep roots. In the early stage, the growth is very vigorous, but this is just an illusion, and when the fruit expands in the later stage, the supply of nutrients and water will be lacking, and the old leaves will turn yellow and wither, and gradually move forward. It is because the plant has the characteristics of top-facing and preferential supply for reproduction, and I am starving to death by adjusting and blocking the water and nutrients of the old leaves at the back!

3.Fertilizer Cause:

In order to increase the yield of watermelon farmers in greenhouses, a large number of fertilizers are used, and the soil is seriously salted, resulting in the root system can not be stretched, the function is reduced or is very weak, and the growth is normal when there is no fruit in the early stage, and the nutrient and water requirements increase in the later stage, and the phenomenon of premature plant aging will appear.

To sum up: melon farmers should use organic fertilizers and fungi as much as possible when planting, increase the content of organic matter and adjust the pH, so that the soil can be restored. After planting, control the amount of water to make the root system stretch deep into the soil.

Try to increase the light and ventilation time, so that the plant can grow vigorously and harmoniously, and lay a good foundation for future consumption.

This situation may be caused by improper fertilization, which is easy to burn, and the roots of the calendar type may also be caused by salt in the soil or herbicides and other drugs.

It may be caused by the heavy use of chemical fertilizers, or there is a lack of elements, or it may be caused by the lack of appropriate medicine.

Watermelon can not be replanted, which is easy to cause a lack of nutrients, resulting in watermelon yellow leaves, and the soil with heavy salinity is used to reduce salinity and alkali with a conditioner to prevent watermelon yellow leaves.

Hello, cucumbers are yellowing for the following reasons:

1. Changes in the external environment.

When there is a sudden change in temperature, humidity and light, it will cause the physiological yellowing of cucumber leaves.

The control method of this situation is: make the growth environment of cucumber meet the growth needs of cucumber, cucumber is a typical thermophilic plant, and its fertility suitable temperature is 10 32.

2. Too much water.

The leaves of cucumber plants are generally yellow, especially the top leaves are small, the growth is slow, and wilting will occur in severe cases.

The most suitable soil relative humidity for cucumber is 85% 90%, cucumber has a strong ability to adapt to air humidity, and the relative humidity of the air at night can reach 90% 100%, but the humidity is too high and the time is too long, it is easy to cause diseases.

Do not water cucumbers more than once to prevent the root system from growing properly due to lack of oxygen due to too much water and causing the root system to rot.

3. Excessive fertilization.

Although there is a lot of demand for nutrients in the process of cucumber planting, it can not arbitrarily increase the amount of fertilizer, if too many nutrients will cause excess nutrients in cucumber plants and cause yellow leaves, therefore, cucumber fertilization needs to be carried out according to different growth stages.

Seedling stage generally top dressing once or twice can be, in the late stage every 10 15 days or so to apply once to meet the demand for nutrients, the fast-acting water-soluble fertilizer is faster than the traditional fertilizer absorption, the effect is also fast, and the yield is obvious. Of course, it is essential to plant cucumber before base fertilizer, pay attention to apply more organic fertilizer and microbial fertilizer.

4. Lack of medium and trace elements.

Cucumbers also have a lot of demand for trace elements, such as magnesium, boron, iron, zinc, calcium and other trace elements.

Amino acid-containing foliar fertilizer can be sprayed in Hai and Weihai to comprehensively supplement the nutrients needed for cucumber growth, so as to improve the quality of cucumber plants and cucumbers, and enhance the resistance of cucumber plants to common diseases.

Hello watermelon leaf blight. It is manifested as true leaf damage, which mostly occurs between leaf margins or leaf veins, and is a water-stained spot at first, which quickly merges and penetrates under high humidity, causing the leaves to lose water and wither. In hot and dry weather, a round brown spot with a diameter of 2 3 mm is formed, and when the weather is humid, it can be combined into a large brown spot, and the lesion becomes thinner, and in severe cases, it causes leaf wilt.

The stems and vines are damaged, producing oval or fusiform, slightly depressed light brown spots.

Summary. 3. Pest and disease hazards.

At the same time, if the larval pests or formed pests are concentrated on the leaves of the watermelon, so as to absorb the leaf juice, especially the young leaves and flower buds that have not yet grown up, if they are damaged, the leaves will turn yellow, and in severe cases, the leaves can dry up.

What's going on with watermelon leaves starting to turn yellow and wither?

1. Because of the use of foliar fertilizer containing hormone substances or the long-term use of a large amount of chemical fertilizer, it will burn the root of the watermelon leaves, so that the leaves will be ossified, faded, yellowed and other phenomena, causing damage to the watermelon.

2. Lack of micronutrients Watermelon's ** and planting benefits are relatively good, and with the increase of the temperature in spring, the demand of people will also increase, which will allow watermelons to multiply in large quantities, which will easily cause the lack of trace elements in watermelon, and it is easier to lack potassium, calcium, boron, such as the lack of these trace elements will lead to different degrees of yellow leaves of watermelon.

3. Pests and diseases harm the larvae at the same time, if the pests or formed pests are concentrated on the leaves of the watermelon banquet core, so as to absorb the leaf juice, especially the young leaves and flower buds that have not yet grown up, if they are damaged, the leaves will be yellow, and the severe infiltration can make the leaves dry up.

The above are the reasons why I may cause the watermelon leaves to turn yellow and wither. You can refer to it, and then prescribe the right medicine, I hope it will help you, I wish you all the best.

Summary. Hello, I'm glad to answer for you, watermelon leaves turn yellow and wilt with the following points.

1. Yellow leaves caused by improper use of fertilizer and root burning Long-term use of a large number of chemical fertilizers has caused more fertilizer to hurt the roots. There is too much use of inferior foliar fertilizer, which causes watermelon hormones and cost damage, making the leaves green and yellow. When using chemical fertilizers, it is best to adopt formula fertilization, and appropriately increase phosphorus and potassium fertilizers.

Second, the herbicide caused by the yellow leaves of the watermelon field generally use post-seedling herbicides, transplanting to strictly grasp the order of operation, flat ridge spraying herbicides, and then digging holes and planting.

The watermelon leaves turn yellow and then start to wilt.

Watermelon leaves are yellow and speckled.

Hello, I'm glad to answer for you, watermelon leaves turn yellow and wilt with the following points.

1. Yellow leaves caused by improper use of fertilizer and root burning Long-term use of a large number of chemical fertilizers has caused more fertilizer to hurt the roots. There is too much use of inferior foliar fertilizer, which causes watermelon hormones and cost damage, making the leaves green and yellow. When using chemical fertilizers, it is best to adopt formula fertilization, and quietly increase phosphorus and potassium fertilizers appropriately.

Second, the herbicide caused by the yellow leaves of the watermelon field generally use post-seedling herbicides, transplanting should be strictly Qiliang stupid to grasp the order of slag, flat ridge spraying herbicides, and then digging holes and planting.

Hello may be plant malnutrition, when encountering low temperature and weak light or premature melon production, there is a shortage of nutrients in spring, resulting in the internal competition for nutrients within the melon plant, resulting in the growth of the melon plant weakened.

1. The yellowing of watermelon leaves is generally caused by improper fertilization, lack of nutrients, pests and diseases, etc.

2. Improper fertilization: the use of unrotted farmhouse fertilizer or long-term use of a large number of chemical fertilizers, resulting in more fertilizer and root burning; Or excessive use of inferior foliar fertilizer, resulting in hormone poisoning of the plant, so the leaves will be green, yellowing and other phenomena.

3. Lack of nutrients: due to the lack of potassium, calcium, boron and other elements in the soil due to continuous cropping, the plants will have yellow leaves.

Watermelon is one of the most popular fruits in summer. However, sometimes you may find that the watermelon leaves are starting to turn yellow and wilt, which means that your watermelon plant may be suffering from some kind of disease. So, what causes watermelon leaves to turn yellow and wilt?

This can be due to a variety of factors.

First of all, pathogen infection is one of the main causes of yellowing and wilting of watermelon leaves. Common pathogens include fungi and bacteria. For example, root rot causes the roots of watermelon plants to rot and can spread to the leaves.

Leaf blight is also a common disease that causes the leaves to gradually turn yellow, eventually leading to wilting. In addition, viral infections, fungal infections and aphids can also cause watermelon leaves to turn yellow and wilt.

Secondly, overwatering may also cause watermelon leaves to turn yellow and wilt. Watermelons need the right amount of water, but if over-irrigated, moisture can accumulate in the roots, causing the plant to not breathe. As a result, overwatering can cause the leaves to turn yellow and wilt.

Finally, poor soil quality can also affect the growth of watermelons. The lack of nutrients, toxic substances, heavy metals and other elements in the soil will make the watermelon leaves yellow and wilt. Before planting watermelons, be sure to test and improve the soil to ensure that the soil quality is good.

In summary, the yellowing and wilting of watermelon leaves can be caused by a variety of reasons, including pathogen infection, overwatering, and poor soil quality. In order to avoid the watermelon plants being affected by the disease, they should be sprayed with fungicides regularly, watered in moderation, and choose good soil to ensure the healthy growth of watermelon plants.