The grape starts to dry out and stops growing. Why do grape leaves dry

It is very annoying when the grapes start to wither at the very finish line.There are several reasons for this phenomenon. You need to learn to distinguish them from each other in order to save the harvest of berries.

Sunburn

The most common cause of withering in a vineyard is sunburn. He acts in different ways. Sometimes the berries simply burn in the sun, in which case they turn brown and taste like fermented.Sometimes - they just wither slightly, without changing the color. This, however, is also not easier: their taste changes, a fermented taste appears.Such grapes are no longer suitable for sale and for food.

To save the harvest, contrary to the recommendations, the bunches are not lightened, and even the stepsons are specially left in the area where the brushes are located.

Mildew

This disease causes the greatest damage to the crop during flowering, when whole clusters of grapes dry out. Then, due to mildew, individual berries dry out, and before ripening, parts of the bunches may dry out.Usually the bottom third or half of the bunch withers.The reason is simple - the fungus blocks the flow of food through the bunch, and below the site of the lesion, all the berries wither.

To prevent this from happening, the bushes are sprayed with mildew three times: before flowering, after and over the "peas".It is better to use systemic copper-containing drugs - Ridomil, Ordan, Kurzat, Polykhom, Acrobat.

Oidium

It can also cause wilting and drying of berries.Although it is more often disguised as sunburn, when a barely noticeable grayish-white bloom appears on the berries, as if a tan from the sun. After that, the berry either bursts or withers.

It's easier with oidium: that you can fight it right up to harvesting using colloidal sulfur or Tiovit.The only difficulty is that these drugs at temperatures above 35 ° C cause burns on the grapes.

Moisture deficiency

The grape is considered a drought tolerant plant.It does tolerate drought really well, but sometimes reacts to it by drying out the bunches. Berries due to lack of water shrink and dry out. Some bunches may dry out completely.

Usually grapes during ripening are not watered until the harvest is complete. But in dry weather, watering is still necessary.

Interestingly, grapes react in this way not only to a shortage, but also to an excess of moisture. In swampy areas, the wilting of the bunches is also observed, similar to a moisture deficit.

Harvest overload

If too many brushes are left on the bushes, they too can begin to fade without having collected sugar. Therefore, it is important not to be greedy, remove unnecessary bunches and carefully regulate the load of the bushes with the harvest.

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Many gardeners grow grapes in order to have a storehouse of vitamins and valuable substances in their area. And just a delicious dessert on your table. But not many beginner growers know how to properly care for the bushes so that they give a good and tasty harvest. After all, gardening is constant work and the fight against pests that strive to damage the grapes or the bush itself.

Often foliage turns yellow and falls off in grapes. Why do the leaves dry, what to do to prevent this?

The reasons why the foliage of grapes dries

When planting a grape seedling, it is necessary to take into account many features and choose the right varieties for your site. If you want to preserve the harvest, and subsequently the entire bush, it is necessary to establish why the grape leaves are drying. Depending on the reason - you can choose the right "treatment" for the plant.

Grapes - a berry bush that does not tolerate sudden temperature changes and is afraid of the cold is very picky about care. Therefore, growing this crop in the north of the country, gardeners are faced with many different diseases.

Covering grapes in late autumn - you can save the bush from frost, but you will get other problems in the growth and development of the bush. Under such a protective layer, the air stagnates, which leads to an increase in the percentage of humidity inside. Without fresh air, fungi and microbes form and grow on the shoots of grapes.

Diseases are also facilitated by various factors that appear later on improper care of the plant:

• a small amount of watering;
• lack of light;
• lack of heat.

All this leads not only to drying and falling of foliage and berries, but also to a significant weakening of the grapes themselves.

A diseased plant can not only die, but also infect the rest of the bushes on the site, since fungal diseases are easily transmitted by spores with the help of the wind.

In such cases, replacing all affected bushes with more resistant and easy-care plants can save the garden. If you don't take any action, then very soon you can lose all the grape bushes. The most common diseases for all grape varieties: oidium, bacterial cancer, Alternaria and many others.

• Lack of nitrogen. A common reason why leaves and berries begin to dry out is a lack of fertilizers in the earthen coma, in particular nitrogen. Symptoms of such a disease: first, the leaves become lighter in color, and then dry completely. How to get out of this situation? It is necessary to make nitrogen-containing preparations and continue to monitor the timely application of fertilizers. To prevent this problem, you can buy special powders at the store or add cow dung or chicken dung.
• Small pests. Small insects, almost invisible to our eyes, can cause irreparable harm to the plant. The most common pests of grapes include spider mites, aphids and others. To find them, sometimes you need to arm yourself with a magnifying glass. If you find insects or traces of their presence on your plant, the plant must be immediately treated with special preparations, which are included in the group of insecticides against these insects. Preparations of the acaricide group will help against ticks. An unusual yellow-red color of the leaves will help to detect pests, since the insects themselves are below the leaves.
• 
  

  Diseases. Leaves can dry out not only due to improper care or pests, but also indicate the presence of diseases in the plant. Sometimes these ailments are very common in grapes and can be dangerous not only for the harvest, but also for the plant itself. The most dangerous can be called chlorosis, which occurs in the case of an excess of carbonate in the soil.

  This ailment can be recognized by several signs: the leaves turn yellow, and after a while they begin to fall off en masse. If new foliage grows in their place, then it is much smaller and thinner than the previous leaves. If you do not fight the disease on time, then it affects the harvest, the fruits become smaller and with an unpleasant aftertaste. Chlorosis also negatively affects the growth of young pagons and the entire plant as a whole.

  As a preventive measure, regular loosening of the soil can be carried out, this procedure promotes the evaporation of excess moisture from the ground and better air exchange between the roots.

  
  

The leaves of the grapes dry up, what to do? The main thing is not to panic, but to establish the reason why this is happening. After all, drying occurs for a reason, but later some kind of disease or improper care. And when you find out what negatively affects the foliage and berries, then you will choose the right treatment, which will bring results.

If the grapes are affected by any disease, their yield is significantly reduced. Damage and death of plant shoots is a serious damage to the vines. The pathological process can begin during fruit ripening or before and proceed without visible signs.

Causes of blackening of grapes

All plant diseases can be divided into two types: infectious and non-infectious.

Infectious pathologies - when grapes become infected from other diseased crops with fungal, bacterial or viral pathogens. In the presence of favorable conditions, pathogenic microorganisms rapidly invade healthy bushes. Infectious diseases lead to depletion and a decrease in the fertility of the bushes, in severe cases - to the death of the entire vineyard.

Non-infectious diseases - when there is no transmission of the pathological process from diseased cultures to healthy ones. The main causes of these types of pathologies are unfavorable environmental factors (hail, hurricane, frost, heavy rains), unsuitable soil and improper plant care. Signs of infection of bushes with an ailment of a non-infectious nature:

Non-communicable diseases also negatively affect crop fertility and crop quality.

Infectious diseases

Most often, grapes turn black due to infectious diseases. Some of the most common ailments include:

Waste products of pathogenic microorganisms can be transferred not only from an infected culture to a healthy one, but also with the help of animals, human clothing and water. Infectious agents cause the death of the entire vineyard.

It is important to know the causes and symptoms of pathologies in order to timely determine the disease and begin to fight it.

Mildew

Mildew is the most common vineyard disease. European varieties of culture are especially susceptible to the disease. The causative agent of mildew is a powdery mildew mushroom. It develops in fallen leaves throughout the winter. The spores of the fungus penetrate the leaves of healthy plants through soil and water. Fungi are resistant to frost and damp because they have thick walls.

The propagation rate of mildew depends on temperature conditions. If the ambient temperature is about 25 degrees, then the spores leave the shell and after 5 hours penetrate the foliage. The incubation period of the disease depends on the time of year:

Spores that have penetrated the leaves of the plant cause stains on them. Even an inexperienced gardener is able to notice pathological changes. Initially, the affected parts of the grapes have light, shiny spots. The size of the formations increases in size over time, and under the spots, on the back of the leaves, a light bloom forms - mycelium.

Oidium

The second most common grape ailment is caused by the fungus Uncinula necator Burr. The primary symptoms of infection are invisible to the naked eye. Then a white bloom appears on the leaves of the grapes. Fungi do not need moisture for reproduction, the main condition is a suitable ambient temperature - from 5 to 30 degrees. Therefore, the disease progresses during the dry season or after the end of the warm winter.

You can understand that a grape is infected with a fungus by the appearance of its leaves. Above them, a raid of a pale gray hue appears. When the plaque is erased, the plant will begin to spread a putrid odor. It should be noted that only young vineyards suffer from the disease. Bushes on which fruits have already formed are resistant to powdery mildew.

The incubation period of the fungi Uncinula necator Burr lasts from 1 to 2 weeks. The higher the air temperature, the faster they progress. Mold spreads especially quickly in those areas of grapes that are not sufficiently ventilated.

The fungi of the pathogen actively spread in the spring, when the air temperature warms up to 8 degrees.

During this time, they carry their spores with the wind, insects and raindrops. Spores caught on a plant can germinate into its cells only under certain conditions:

The leaves of the plant are affected by black rot mainly in June. Young bushes are especially susceptible to the disease. Their green parts are rapidly covered with black blotches of a rounded shape. The edges of the affected areas harden, resembling scabs in appearance. Gradually, symptoms of infection appear on the crests of the plant, its inflorescences and fruits.

Anthracnose

Another reason for the blackening of grapes is the fungal disease anthracnose. It spreads with heavy rains, hail, actively multiplying in a humid environment. The increased activity of fungi is observed at temperatures from 2 to 30 degrees. In one season, anthracnose can give up to 30 generations.

Young leaves of grapes are affected by the disease through mechanical damage. Anthracnose has its own distinctive features:

Gardeners often confuse these symptoms with hail damage. The main difference is that when a disease occurs, the edges of the black spots rise.

Bacterial cancer

This ailment is feared by gardeners around the world. Since the disease affects almost all grape varieties, leading to their blackening and death. Bacterial cancer is especially common in cooler regions. The culprit of the disease is the bacterium Agrobacterium tumefaciens.

There are many reasons why a plant becomes infected with bacterial cancer:

Cutting the outgrowths with subsequent processing does not work. Spreading bacterial cancer cannot be cured by any means. The best solution in this case is to uproot the affected bush and burn it.

No other crops should be planted in place of an infected plant for 5 years.

Non-communicable diseases

Non-infectious pathologies are manifested most often due to non-compliance with the rules for caring for crops. Diseases of a non-infectious nature arise from:

All these factors negatively affect the life of the grape bushes. But unlike infectious diseases, they are easily eliminated without the use of means for processing and disinfecting plants.

Bending and drying of ridges

Some types of grapes with large varieties of berries are prone to this state - hybrids. It is easy to avoid creases if you provide the bush with support on an arch or a gazebo. So the hanging bunches can develop well, and the load on the branches will be evenly distributed.

If the plant does not show signs of infection by fungi or bacteria, but still turns black, one can suspect that its ridges are drying out. Drying of the ridges does not extend to neighboring crops and is most often associated with insufficient moisture ingress to ripening fruits.

Covering bushes in winter can lead to drying of the ridges. Under the cover, the plant is poorly supplied with oxygen and is constantly in conditions of high humidity.

Non-infectious chlorosis

The disease occurs due to a lack of iron in the soil. Sometimes the element is present in sufficient quantities in the soil, but it is poorly absorbed by crops. Frequent feeding provoke an excess of potassium in the soil and it begins to displace other useful trace elements - magnesium and calcium.

The reaction of iron and excess calcium makes the former indigestible for crops.

The disease also provokes the accumulation of hydrogen sulfide in the soil. Most often, vineyards located on heavy soils, which poorly receive oxygen, suffer from the disease. Impaired air exchange causes weakening of the bushes. Berries on it begin to peas without ripening. Such bushes die in the winter. Untimely measures lead to the death of the entire crop, because the composition of the soil is the same throughout the planting area.

Treatment methods

Grapes turn black quickly, and you need to know what to do to prevent the putrefactive process. Culture treatment interventions will depend on the type of disease.

Mildew treatment

For the purpose of prevention, healthy bushes are treated with drugs:

• Cuproskat;
• Strobe;
• Antrakol.

To prevent mildew from damaging the vineyard, the soil is fertilized with potassium and phosphorus. Stepchildren are removed from the grape vine, so that all its strength is spent on ripening the fruit.

Oidium treatment

This type of fungus can no longer tolerate a constant supply of fresh air. Therefore, simple agrotechnical methods will help to remove oidium:

When treating oidium, grapes are sprayed with drugs: Thanos, Horus, Topaz. This reduces the spread of fungi.

Black spot treatment

In order to prevent the development of the disease, preventive spraying is carried out in early spring. For the procedure, fungicides are used. The procedure is repeated 2 times during the season, combining it with powdery mildew and mildew treatment.

The main rule for the prevention of black spot is the timely removal of shoots.

The cut sites are treated with solutions so that in the future they do not become vulnerable to the fungus.

Anthracnose treatment

The disease is difficult to treat. But with regular treatments, the likelihood of its development decreases. For spraying bushes use:

Processing is carried out after heavy rains. Twice the grapes are treated with fungicides - before flowering and during fruit ripening.

The general treatment regimen is as follows:

• before the appearance of buds, the grapes are sprayed with preparations containing copper;
• before flowering vines, plants are treated with Topaz or Strobi preparations to protect against mildew and iodium;
• after a few weeks, the bushes are sprayed from insect pests with Quadris or Bi 58;
• unripe fruits are treated with fungicides;
• during the dyeing of the berries, they refuse chemical treatments of the plant.

If there is an unfavorable infectious background, the treatment of crops is continued after the harvest.

To grow a vineyard on your plot is, perhaps, many gardeners dream about. But you will need to work hard, since this plant must be treated in a timely manner from various infections and pests. Nevertheless, brown spots on the bunches of grapes are not uncommon, even taking into account the timely replenishment. Why grape berries rot and dry, and how to prevent it - this is what you need to understand before starting your vineyard.

Main reasons

If dark spots appear on the grapes, then the key factor that caused this result is not always the same. For example, if your vineyard has been affected by infectious diseases, the pathogens may be fungi, viruses or pests. Much also depends on the characteristics of your care.

Frequent mistakes can become, if not the key cause of an illness, then at least contribute to it. We must not forget about the possible mechanical damage to the branches and foliage of the plant, as well as about the climatic conditions in your particular region. All this as a whole can cause the development of certain ailments. If dots or specks appear on the berries, it's time to figure out what exactly you are dealing with this time.

Infectious diseases

When pathogenic microorganisms get on the foliage or grapes, the disease begins to develop rapidly. Soon you will notice how small spots on the fruits increase in diameter, and the berries become lethargic, turn black and dry out. Interestingly, there can be several ways to infect shrubs. Spores are not necessarily transferred from a diseased plant to a healthy plant.

Sometimes fungi and other harmful microorganisms get on grapes with the help of animals, human clothing or water. If the green fruits of the grapes turn black, be sure to consider the most common ailments of an infectious nature:

• mildew or downy mildew. These microorganisms can easily overwinter on plant debris, and with the onset of spring, their spores are carried by the wind. This disease primarily causes serious harm to the grapes. They soon begin to darken, and the foliage curls and can dry out;
• anthracnose. With the development of this disease, absolutely all parts of the bush wither and dry out. Initially, the foliage and shoots of the plant are covered with brown spots with a dark border. If the stem of the bush has suffered from anthracnose, it is recommended to cut and burn all the affected areas as soon as possible. If this is not done, the plant will lose up to 70% of its foliage;
• black spot. If the grapes turn black soon after the rain, it is obvious that this ailment was the cause. In the future, it will spread to foliage and shoots. You can correct the situation with Bordeaux liquid. Shrubs are sprayed with it.

Knowing what to do if dark spots appear on the grapes, and the leaves change color or dry out, you can save your plants from death.

Non-communicable diseases

Let's say the grapes began to turn black and dry. The cause is not always an infectious disease. Sometimes it turns out to be the mistakes you made in caring for the plants. For example, excessively bending the ridges of a shrub will help them dry out. The lack of moisture affects the grapes not in the best way. That is why watering the plant during the growing season is mandatory.

The unfavorable factors also include heavy soils. If yellowish spots appear on the leaves of the grapes, it is quite possible that this is non-infectious chlorosis. You will be able to eliminate the problem if you apply mineral fertilizers to the soil in a timely manner.

Grape cure

When the reasons for the drying up of the vineyards have been clearly identified by you, it's time to start treating the disease. The optimality of a particular method will depend on the disease itself. For example, if your shrubs have been infected with mildew, they must be uprooted and then burned without fail. Otherwise, the disease will spread to healthy grape bushes.

Let's say your vineyard has suffered from black spot. In this situation, it is much easier and cheaper to start prophylactic treatment of the plant in a timely manner. For this, special fungicides are used, with which the grapes are sprayed at least twice a season. So that black spot does not become your problem anymore, it is worth adhering to the key recommendation: unnecessary or damaged shoots of the plant are immediately removed, and the cut sites are treated with a special tool.

Anthracnose is difficult to get rid of, so prevention is the best solution for you.

It is recommended to spray the bushes twice during the growing season (before the beginning of the flowering phase and in the process of fruit ripening). Do not forget that the treatment will be effective if you apply medicine after rains. When it is time to harvest, it is better to postpone the spraying of the bushes. But if the problem has not been completely eliminated, it is recommended to continue treatment in the autumn period.

Prophylaxis

Blackened bunches of grapes are far from the most desirable result for any grower. However, if an infectious disease already affects the entire shrub, it is difficult to cure it. Therefore, experts, as a rule, recommend timely preventive treatment. For this, special preparations or Bordeaux liquid are used.

Monitor the condition of your vineyard from the beginning of the growing season. Examine the bunches and foliage of the plant regularly for blackheads, spots, or dried parts. If you devote enough time to this, then you will not need to look for ways to treat infectious or non-infectious ailments. Save the grapes from rot, and you can enjoy their taste.

Video "Diseases of grapes and the fight against them"

In this video, you will learn about grape diseases and how to treat them.

Another favorite culture of gardeners is grapes, as they are easy to care for, and the fruits are tasty and healthy. Even with the correct planting of seedlings and with proper care, a garden culture may not please you every year with a bountiful harvest. You may face such a problem as wilting of leaves, berries, brushes.

In this article, you will find out why grape clusters wither and dry out, and what measures will help prevent this process.

Under some circumstances, it can dry from half to the entire crop

Establishing reasons

In order to timely stop the drying process of grape bunches, it is important to determine the reasons. Common reasons include:

• A large amount of ultraviolet radiation.
• Defeat by mildew.
• False sunburn or powdery mildew.
• Insufficient moisture.
• Overweight of bunches.
• Defeat with gray mold.
• Chlorosis damage.
• Insufficient soil fertilization.
• Invasion of pests.

Gardeners must be able to discern the reasons in order to properly organize the process of vineyard restoration. For this, we will characterize each of the reasons.

Sunburn causes the berries to gradually dry out

A large amount of ultraviolet radiation

A large amount of ultraviolet radiation forms a burn, which affects not only the bunches, but also the leaves and berries. Sunburn can be of several degrees, and with mild damage, growers may not determine the cause in time. It is important to pay attention not only to the color of the berries, but also to their taste. With a severe burn, the berries will change color, with a mild or moderate burn, the berries retain their color, but the taste changes regardless of the level of damage.

Ultraviolet damage is a common cause, it is recommended not to lighten the clusters, to leave stepchildren in the area where the brushes are located.

Defeat by mildew

A terrible disease, which is the reason why the bunches of grapes wither and dry up, there is a mildew fungus. The disease begins to actively attack at the time of flowering grapes.

The mildew of the grape makes the harvest completely unusable

It affects with mildew both individual sections of the vineyard: berries, brushes, and whole clusters. The disease is dangerous because the infected area blocks the access of food, moisture to healthy areas, the garden culture begins to dry out. In order to avoid injury, it is recommended to use the drugs "Ridomil", "Ordan", "Polykhom". Prevention should be carried out three times: before flowering, at the flowering stage, a month before harvesting.

Tip: in order to get a good harvest, choose the right variety that suits your area of ​​residence. The land needs to be fertilized, loosened, watered in a normalized manner. Plant dill near the vineyard.

False sunburn or powdery mildew

Even an experienced winegrower does not always correctly determine why the grapes wither, and this also affects the methods of struggle. It is important to correctly determine what affects the vineyards - sunburn or powdery mildew. As with a large amount of ultraviolet light, the berries are affected, they acquire a gray bloom, and the clusters begin to dry out. It is possible to fight against powdery mildew until the harvesting stage. It is recommended to use colloidal sulfur.

Oidium grapes completely destroys bunches

It is important to take into account that a number of agents, and sulfur too, have a negative effect on vineyards at air temperatures above thirty-five degrees.

Insufficient moisture

Growers love garden culture because it does not require special care, it tolerates drought well, and does not require a lot of drinking. But, this is not a sign that the grapes do not need to be watered, since the lack of moisture in the soil can cause the grapes to dry out. In the absence of water, the entire vineyard suffers, and the leaves and berries become sour in taste, decrease in size. Brushes may dry out completely. If the summer is humid, then you can water the vineyards after harvesting. During periods of drought, abundant watering should be organized frequently.

The lack of moisture appears on the leaves and berries.

An interesting fact: if the vineyard is located in a swampy area, then the brushes may also wither, as if there is a lack of moisture.

Overweight of bunches

A large amount of harvest, berries, can be the reason why vineyards wither. It is important that there are not many brushes on the bushes, because there will be an uneven distribution of sugar. It is recommended to remove excess clusters, to control the load on the bush.

But high-yield varieties need to ration the number of bunches.

Defeat by gray mold

A common disease that affects vineyards in spring is gray mold. Spring is a period with high humidity and warm air, and this is the optimal environment for the development of the fungus Botrytis cinerea. Gray rot completely covers the bushes, and it is recommended to start the fight at the first sign. Healthy areas do not receive moisture, minerals, bushes begin to dry. This is a dangerous disease, which is the reason why the bushes wither and dry, has no effective ways of fighting.

Gray rot is a dangerous bacterial disease

Since the affected areas need to be cut and burned, and this, with an untimely struggle, leads to the destruction of an entire bush or a number of vineyards.

Botrytis cinerea is found in all regions; it is important for winegrowers to prevent horticultural crops. To do this, dilute a small spoonful of soda in one liter of water, spray the bushes with the solution. There is also a positive side to the fungus. If you need to get an elite wine, then the fungus is specially applied to the fruit, because the disease increases the sugar level in the berry.

Chlorosis damage

In the presence of a large amount of carbonate in the soil, chlorosis occurs, which becomes the reason why the grape bushes dry out. The disease is actively developing in early spring and in the second half of the summer period. The whole bush suffers from chlorosis.

Chlorosis of grapes can cause drying out of ripe bunches

Insufficient soil fertilization

With an insufficient amount of nitrogen in the soil, the bushes will dry out. Initially, the leaves suffer, they acquire a light shade, and the bunches dry out. In order to prevent wilting, it is recommended to fertilize the soil with chemicals that contain nitrogen or chicken, cow dung.

Invasion of pests

Insects are a common cause. Vineyards are affected by aphids and spider mites.

Phyloxerous mite on the roots of grapes

The size of the pests is small, it is difficult to see them with the naked eye, and this will not allow you to determine the invasion in time and choose the right way to fight. If you see insects spoiling the bushes, use injections. To combat spider mites, it is recommended to use acaricides.