The question of why cucumber leaves dry out is one that almost every second summer resident often asks himself. The fact is that there can be many reasons for this phenomenon, and it is not always possible to immediately find out why this happens. It is necessary to deal with the problem only after finding out the reasons, then the measures taken will be effective.
As a rule, they do not keep themselves waiting long if the climate changes dramatically. For example, the weather is sunny, dry and hot during the day, and very cold at night. Rains make the situation worse. Especially if the cucumbers are grown in an environmentally polluted area.
Fusarium is one of the most common fungal diseases of cucumbers. Rusty dots begin to appear on the leaves, which gradually increase, turning into spots. As a result, the leaves dry out completely and fall off. It should be noted that the lashes become sluggish, but do not react in any way to abundant watering.
Often, along with fungal diseases, cucumbers are affected by pests. Whiteflies and aphids are the most common ones. Summer residents often do not notice them, since these insidious insects settle in the lower parts of the leaves. As a result, the foliage quickly turns yellow, then dries and dies, as pests simply suck all the nutrients from the plant.
Natural causes of drying leaves
This is especially true for large greenhouses and open areas where cucumbers are planted close to each other. This is a completely natural process, so there is no need to worry about it. On the contrary, experts recommend cutting off the lower leaves with pruning shears from time to time so that the plant does not waste nutrients on them. Let it better devote more energy to the formation of juicy fruits.
In some cases, yellowing of the leaves is due to the natural aging process of the vines. As a rule, large leaves that have been growing on the vine for quite some time begin to dry out. They can be located both at the top and at the bottom. The only thing you should be wary of is if the leaves die on very young cucumber vines.
Inappropriate fertilizing and watering
This is quite rare, since most gardeners still prefer to feed the plants abundantly, believing that this will increase the amount of harvest.
If pale veins appear on the leaves with a yellowish tint, this may indicate a lack of iron or manganese in the soil. If the upper leaves, which are still quite young, actively turn yellow, this indicates a lack of copper. But yellowing of the edges of cucumber leaves along the contour indicates a lack of nutrients such as magnesium and potassium in the soil.
So, if the leaves first turn yellow and then dry out quickly, this indicates insufficient watering. When there is a lack of moisture in the ground, the roots of cucumbers gradually begin to move closer to the surface of the earth. As a result, the entire vine begins to dry out along with the fruits. If the leaves begin to turn yellow and then rot, this already indicates an excess of moisture.
This usually happens if, in hot, dry summers, the intervals between waterings increase, as a result of which the overdried earthen ball can remain in such a solid state for a long time. Or if the plants are watered frequently and abundantly, but the weather outside is not very hot.
Why do cucumber leaves turn yellow (video)
How to prevent leaves from turning yellow
What to do if the leaves of cucumbers dry out in a greenhouse or in a summer cottage?
It is urgent to take some measures, otherwise the harvest may not be saved at all. But it is best to prevent this process in time, without taking it to extremes. Therefore, it is extremely important to follow all preventive measures to ensure that the cucumber leaves do not begin to turn yellow.
It is recommended to water the cucumbers as needed when the earthen ball is completely dry. Fill the soil well so that it is soaked to a sufficient depth. After watering, it is recommended to cover the soil around the cucumbers with dry grass or leaves, which will retain moisture in the ground and provide the roots with additional warmth and an influx of nutrients.
Fertilizers must be alternated, since otherwise an excess of nutrients can lead to rapid development of leaves and absence of ovary. Wood ash is an excellent fertilizer and at the same time a medicine against fungal diseases. You just need to sprinkle it on the ground around the plants.
Another good option for preventing fungal diseases is a baking soda solution. It is necessary to dilute approximately 1 tbsp. soda in 10 liters of water and water the beds with this solution. This should only be done at the end of June and July. An alkaline environment will not give any chance for the development of pathogens in the soil.
In order to stop the process of yellowing and drying of leaves on cucumber vines, it is recommended to spray them with a very weak solution of potassium permanganate or kefir. 2 liters of kefir are diluted in 10 liters of warm water. The resulting composition is sprayed onto the leaves, fruits and stems of cucumbers. Such spraying can also be carried out for preventive purposes, since they do not cause any harm to plants or people.
So, why the leaves of cucumbers turn yellow in a greenhouse and in an open area is now clear. In any case, all dried leaves should not be spared and should be torn off. After all, if the cause lies in a fungal infection, it can easily spread to other shoots and plants.
Diseases of cucumbers and their control (video)
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Cucumbers are grown by almost all gardeners, both experienced and beginners. The technology for growing this crop is known to everyone, but nevertheless, in many areas every season a problem arises - the leaves of cucumbers wither. Let's try to figure out why this happens.
The first and most common reason why cucumber leaves wither is a simple lack of moisture. If a plant does not have enough water, its leaves will first droop, wither, and then begin to dry from the edges to the center. How to determine that the cause is a lack of water? It’s very simple - start moistening the beds every day, morning and evening, and if the situation quickly changes for the better, then the problem was only in the wrong watering regime.
The second reason why cucumber leaves wither is directly related to the first. If you planted tomatoes and cucumbers in the same greenhouse, such proximity will not lead to anything good. Despite the fact that both plants are heat-loving, cucumbers require high air humidity, which tomatoes cannot tolerate at all. That’s why it may turn out that, trying to please the tomatoes, you “overdried” the cucumbers, and they again suffer from a lack of water.
The third reason why cucumber leaves wither is when herbicides get into the garden bed. Cucumbers cannot tolerate them at all, so you should not use chemicals not only in the greenhouse, but also in neighboring beds. If the herbicides have already managed to reach the plants, then abundant watering will help - the chemicals will simply be washed off with water and go further into the soil.
Another reason why cucumber leaves wither is aphids. It is very easy to confirm or refute this - you need to look at the back of the sheet. If you find aphids there, then you need to take urgent measures, since the pest can infect all healthy plants in a matter of days. It is best to use a soap solution or special chemicals, such as Iskra or other similar preparations. In addition, cucumbers may suffer from fungal disease or mites. The first is eliminated using chemicals such as “Photosporin”, and the second is eliminated by using an infusion of onion peels.
The last reason why cucumber leaves wither is incorrect agricultural technology, that is, a whole complex of factors that affect the plant to one degree or another. For example, excess or lack of fertilizer, incorrectly chosen planting location, when direct sunlight actually burns the leaves. This can also include incorrect watering technology, when plants are watered often, but little by little. As a result, water does not reach the roots, and the plant begins to suffer. Another watering mistake is spraying water directly onto the leaves on a bright sunny day. Droplets of water turn into tiny lenses and the cucumbers get burned.
So, we have enlightened you on the question of why cucumber leaves wither, and have indicated the most effective methods of combating this phenomenon. Take care of your plants, and they will delight you with a tasty and rich harvest.
Why do cucumber leaves wither in a greenhouse and in open ground? One of the reasons for this unpleasant phenomenon may be a fungal disease called Fusarium wilt of cucumber, which mainly affects plants in greenhouses.
The first signs of this disease are wilting of the top of the plant and individual leaves. The wilting process is also accompanied by rot of the stem in its root part. During the flowering phase and at the very beginning of fruit formation, the roots and root collar of cucumbers become brown, cracks appear on their bark, which soon rot. If you cut a cucumber stem in the root zone, you can see a ring of browned vessels.
If growing conditions are too wet, a pink coating may be observed on the stems of diseased plants and on the soil next to them. This plaque is an accumulation of pink conidia - the causative agents of the disease.
The causative agent of this disease penetrates cucumbers through wounds in the roots and root hairs. The disease is most dangerous when the soil temperature drops below 10 - 15 degrees.
The main source of plant infection with fusarium is contaminated soil. The fungus gets there along with plant debris and can persist there for quite a long time. The fusarium fungus is also transmitted by seeds.
Based on the above, it is clear that the main methods of combating fusarium wilt of cucumber are soil disinfection and seed treatment before sowing. Heavily infested plants must be removed and destroyed. Monitor the maintenance of optimal temperature and humidity values in the greenhouse. Do not water cucumbers with water at temperatures below 22 degrees.
It is worth noting that cucumber leaves wither not only because of this disease. Other causes of leaf wilting.
Cucumbers are one of the most popular vegetables that are eaten throughout the year, so they are grown both in greenhouses and in open ground in almost every garden plot. But sometimes, despite the fact that the gardener follows all the recommendations, for some reason the leaves of the cucumber wither. Let's determine the main causes of this problem.
Chapter 1. Causes of fusarium disease
Gardeners have identified the following main reasons why cucumber leaves wither:
Failure to comply with growing conditions:
watering - insufficient moisture leads to the fact that the leaves begin to dry from the edges to the center, and you should also avoid getting moisture on them;
small distance between plantings;
incorrectly selected location - if direct rays of the sun fall on the cucumber leaves, then most likely they will begin to wither very quickly. The shape of the beds on which this crop is planted is also of great importance - too narrow and high lead to loss of necessary moisture, which leads to withering of the leaves and stems;
oversaturation or lack of fertilizers;
ingress of herbicides - since this plant does not tolerate them at all;
inappropriate neighborhood, namely tomatoes planted nearby, since these plants need different air humidity.
Weather conditions - this delicate plant is very sensitive, therefore it reacts to sudden cold snaps.
Diseases and pest infestations:
fungal disease - fusarium wilt of cucumber, affecting greenhouse plants. It can be distinguished by a withered crown, accompanied by stem rot in the root zone;
white rot - leaves lose their turgor, become completely soft, and then completely fall off, brown spots form in the root zone;
root rot is the main reason why the lower leaves of a cucumber wither and dry out; if not treated in time, the whole vine dies;
aphids - you can find them on the back of the sheets;
ticks.
Having determined the reason why the cucumber leaves began to wilt, measures should be taken to save the plant, since this condition can lead to its death.
If the cause is insufficient watering, then it is necessary to start watering the bushes as quickly as possible, often and in large quantities, so that the moisture reaches the roots of the plant. In this case, you need to ensure that the water does not spread, but remains around the stem. To do this, the bed must be level or you can even make it a small funnel.
If pesticides get on the leaves, you should wash off the fertilizer from them as quickly as possible; together with water, they will be absorbed deep into the soil and will not be dangerous for the cucumber.
When leaves wither due to a plant being damaged by a disease, fungus or pests, it is very important to detect this as quickly as possible and treat it with special means: root rot - spray with the drug “Trichodermin”, which is oat grains covered with dry green mold. They are soaked and the resulting solution is used to treat the diseased plant;
aphids - a soap solution helps very effectively, or you can buy special chemicals, for example, “Iskra”;
fungal diseases (fusarium wilt of cucumber or white rot) - it is necessary to resort to the help of chemicals such as “Photosporin”, “Kornevin”, “Gitrauxin”;
mites - spray with onion peel infusion.
To avoid these problems, you should treat the seeds in advance, treat the soil before planting, and also periodically spray the cucumber lashes with a weak solution of potassium permanganate from a spray bottle. Before planting a cucumber in your garden, you should definitely familiarize yourself with possible problems when growing it and methods for eliminating them.
Chapter 2. How to deal with such a disease
The first reason, and the most common one, why cucumber leaves wither is that they lack moisture, i.e. The plants urgently need to be watered. It is better to water the beds early in the morning and in the evening; if this was the reason, the plant will quickly come to life and the leaves will restore their shape. Cucumbers in greenhouses love high humidity. If you do not water cucumbers for a long time, the leaves will quickly dry out.
Cucumbers do not tolerate chemicals; if weeds were controlled with herbicides and they got on the cucumbers, the leaves may droop and wither. In this case, water the cucumbers generously to wash away the chemicals from them and the soil around the plant.
Carefully inspect the drooping leaves from the back side, they may be infected with aphids. If you find aphids, you need to urgently take action - spray the plants with a soap solution or a special “Iskra” solution.
If the leaves of the cucumbers are drooping, inspect the root collar; the plant may be affected by root rot. The root of the plant darkens and becomes rotten. Water does not enter the plant, despite regular watering.
The reason that the leaves wither may be pests.
Fungal diseases are also a common cause of leaf wilting. So, white rot leads to the fact that the leaf becomes more lethargic, becomes covered with plaque and completely disappears. This happens most of all when the fruits have already begun to appear. It is easier to fight fungi by preventing their appearance. It is necessary to treat the seeds before planting and cultivate the soil. Preparations for “white rot” or fusarium lesions - “Fitosporin”, “Kornevin”, “Gitrauxin”.
Many diseases are easier to prevent than to get rid of. For example, spraying a solution of potassium permanganate will save plants from many troubles.
Section 1. Chemicals for wilting cucumber leaves
In order to prevent the disease, it is advisable to maintain the required temperature regime in the greenhouse in May-June, because Plants adapted to heat practically do not get sick. Perhaps, to reduce the symptoms of fusarium, anti-stress drugs, for example Megafol, should be used.
It is recommended to water the soil immediately after sowing the seeds with a 0.15% solution of Previkur Energy with a working fluid flow rate of 2-4 l/sq.m. The same drug protects seedlings from root rot and downy mildew.
There seems to be no disease, but there is a group of drugs used to protect potatoes and tomatoes from Alternaria blight. They are also recommended for cucumber, but for some reason Alternaria is not on the list of diseases against which they are used. Therefore, when treating plants against peronosporosis, it should be taken into account that at the same time it is possible to protect them from Alternaria blight. You can use Acrobat MC and Gymnast, Quadris, Metaxil, Abiga-Peak. The drug Falcon is also effective in the fight against Alternaria blight. The most dangerous pathogen is rare in Russia. Other species, which are normally saprotrophs, usually cause the disease in the autumn. The disease may be associated with mechanical or biological damage to leaves and fruits. The most effective agrotechnical control measures, prevention and improvement of production standards.
Section 2. Folk remedies for wilted leaves
A measure to combat fusarium, or rather even prevent it, especially if you plant cucumbers in a greenhouse, is to soak the seeds or roots of seedlings in a solution of the drug “Fitosporin M”.
From folk remedies: spraying cucumbers with a whey solution (3 liters and 1 teaspoon of copper sulfate per 7 liters of water). You can also spray with pure serum.
After the last harvest, the bed with plants must be treated with a solution of copper sulfate (50 g per 10 liters of water). Sprinkle all the plants generously, and after a day, remove them from the garden along with their roots and burn them.
Grow resistant cucumber hybrids. Cucumbers in greenhouses are watered in the morning.
Soil disinfection. Seed dressing. Destruction of heavily affected plants. Optimal temperature and humidity in the greenhouse. Watering plants with warm (22 degrees C) water.
Chapter 3. Prevention
Treating seeds before sowing with Fitolavin is a good prevention of early damage to cucumber. Preventive treatment of plants with microdoses of copper sulfate reduces the number of plants affected by fusarium by approximately 2 times. It is also important to regulate the relative air humidity in greenhouses within optimal values and to prevent the formation of water droplets. When characteristic leaf spotting appears, plants should be sprayed with a 0.5-0.7% solution of Bordeaux mixture, which delays the development of the disease. Subsequently, the plants are sprayed with a 0.2% solution of Fitolavin. The disease is most harmful in film greenhouses. The development of fusarium disease is promoted by cucumber monoculture, high air humidity, drip moisture and a combination of high daytime and low night temperatures. To protect plants from bacteriosis, it is important to create optimal conditions for plant development, avoid the appearance of drops on the leaves, preventively spray them with biological products, and after the appearance of symptoms - with copper-containing and bactericidal preparations. Bacteria synthesize proteins around which ice crystals quickly form even at low positive temperatures. This feature must be taken into account when carrying out preventive protective work. Infected plants have reduced cold resistance. The pathogen develops well in the temperature range from 12 to 25°C; it can be transmitted by seeds and drops of water during irrigation or rain.
Preventive measures against the appearance of aphids will be timely removal of various plant debris in which insect larvae settle. Treating cucumbers with infusions of various plants helps: tomato and potato tops, celandine, yarrow. Chemical preparations used include Fitoverm, Aktara, and Iskra.
When affected by various diseases such as fusarium, treatment is carried out with drugs such as “Fitosporin-M”, “Topaz”, “Hom”.
As soon as the first signs of root rot appear, it is recommended to sprinkle the vine with earth at a distance of 10-15 cm from the main shoot. As a result, the lash will grow its own roots, which will allow it to be preserved even if the plant dies. If the plants have been severely affected by one of the types of rot, it is recommended to disinfect the soil in the fall, since the bacteria of this disease live in the soil. To prevent the appearance of fungal diseases of cucumber, they are treated with Bordeaux mixture.
Keep your area clean: it is in plant waste that most pests live and multiply.
10 months ago
Some cucumber bushes stand with withered leaves. This is definitely some kind of disease. What kind of disease is it when the leaves on cucumbers wither?
What measures to take to save cucumbers.
10 months ago
In the daytime, even when it is not very hot outside, some cucumbers stand with limp leaves, as if they were boiled. Most likely the issue here is root rot.
If you pull the stem of such a cucumber out of the ground, you will notice that they have rotted and become rotten. The main reason for this phenomenon for open ground cucumbers is cold weather, which is unfavorable for the development of cucumbers. Cucumbers love warmth.
But a drop in soil temperature to +16 degrees or below is poorly tolerated. Fungi and bacteria from the soil attack the plant, and it weakens. Some gardeners water cucumbers with cold water, as a result of which cucumbers get this disease. Control measures, or rather even prevention, especially If you are planting cucumbers in a greenhouse, you can soak the seeds or roots of the seedlings in a solution of the drug "Fitosporin M". Among the folk methods of combating root rot, you can try the following: remove the soil from the diseased stem 5 centimeters and add sawdust or sand, or chalk. They also water the roots with a solution of potassium permanganate. 3-5 grams of this drug are diluted in 10 liters of water.
Comment
Almost everyone who comes to their country house for the summer plants their own garden, where vegetables and fruits are grown that adults and children can safely eat. One of the most popular vegetable crops that is planted by almost all gardeners, both experienced and beginners, is the cucumber. But very often this crop begins to wither, we frantically search for the cause of the problem - why do cucumber leaves wither? First of all, it is necessary to find out what factor can influence the withering of foliage, and there are several of them: agronomic conditions may not be met, the influence of weather conditions or a disease of the crop .Cucumber is a rather delicate plant and will not tolerate careless treatment of its person.
Problems that cause cucumber leaves to wilt.
The most common reason why cucumber leaves may begin to wither is a simple lack of moisture. When the plant is not watered enough or there is a drought, their leaves begin to wither, then they dry out and turn yellow until they completely fall off. As soon as you notice that the leaves of the cucumbers are losing their juiciness and elasticity, just start watering them more often.
This can be done early in the morning or in the evening closer to sunset. But you shouldn’t overwater cucumbers either, otherwise there may be a risk of infection with root rot; everything should be in moderation. If you planted cucumbers in a greenhouse and planted tomatoes next to them, the cucumber tops may begin to wither.
Although both of these vegetables like frequent watering, cucumbers also need high air humidity, and a dry greenhouse climate can cause cucumber leaves to wither. Another reason why cucumber leaves wither may be herbicides on their surface. The vegetable does not tolerate this fertilizer at all, and in order to save the harvest and prevent the plant from dying, it is necessary to generously spill the foliage with water to completely wash off the herbicides. Infestation by aphids can be detrimental to the vegetable; if you notice wilting, pay attention to the back side of the leaf.
When fears are confirmed, there is no time to waste, otherwise this pest will be able to infect all healthy leaves in a matter of days. In order to get rid of aphids, you can use a regular soap solution or buy ready-made products. Since cucumber is a representative of pumpkin plants, it is very susceptible to white rot.
When a plant is infected by this fungus, its foliage becomes softer, becomes covered with mucus and soon falls off completely. Most often, such a disease manifests itself already during the period of fruit appearance, and it can be detected at a very early stage. Pay attention to the root system of the shoot; if brown spots appear on it and subsequently form a solid lump, this is the first sign of white rot.
Since this is a fungal disease, it is easier to prevent than to cure. Even before planting seedlings, cucumber seeds and growing containers should be treated.
The soil also needs to be disinfected and, if possible, completely replaced. In order to grow a good and rich harvest of cucumbers, you must comply with the necessary agricultural technology conditions and care for the plant correctly - in a timely manner. In principle, the simplest solution of potassium permanganate used for spraying will help prevent many diseases . An earthing system can also help, thanks to which fungal diseases will not be able to gain a foothold on the crop. Since cucumber is still a southern crop and its root system is weak, sudden changes in weather conditions can also affect it. To prevent the soil from drying out or the roots from overcooling, you can mulch the soil surface in the place where you planted the cucumber seedlings. Diseases of cucumber leaves wither video. Now you know why cucumber leaves wither, and you can prevent possible causes of death of cucumber foliage.
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Greetings to all friends of gardeners and gardeners! In the comments to articles, my readers often ask the question: “why cucumber leaves wither in a greenhouse and in open ground? One of the reasons for this unpleasant phenomenon may be a fungal disease called “Fusarium wilt of cucumber,” which mainly affects plants in greenhouses. The first signs of this disease are wilting of the top of the plant and individual leaves. The wilting process is also accompanied by rot of the stem in its root part.
During the flowering phase and at the very beginning of fruit formation, the roots and root collar of cucumbers become brown, cracks appear on their bark, which soon rot. If you cut a cucumber stem in the root zone, you can see a ring of browned vessels. If the growing conditions are too wet, then a pink coating can be observed on the stems of diseased plants and on the soil next to them.
This plaque is an accumulation of pink conidia - the causative agent of the disease. The causative agent of this disease penetrates cucumbers through wounds in the root and root hairs. The disease is most dangerous when the soil temperature drops below 10 - 15 degrees. The main source of plant infection with fusarium is contaminated soil.
The fungus gets there along with plant debris and can persist there for quite a long time. The Fusarium fungus is also transmitted with seeds. Based on the above, it is clear that the main methods of combating Fusarium wilt of cucumber are disinfection of the soil and treatment of seeds before sowing.
Heavily infested plants must be removed and destroyed. Monitor the maintenance of optimal temperature and humidity values in the greenhouse.
Do not water cucumbers with water at a temperature below 22 degrees. It is worth noting that cucumber leaves wither not only because of this disease. Other reasons for leaf wilting can be found in the “Plant Diseases and Pests” section.
Cucumbers are withering, what to do?
Wilting of cucumber leaves is one of the common problems that can be encountered when growing this crop. This can be caused by a number of reasons, including fungal diseases.
What to do if cucumber leaves wither? Any representative of pumpkin plants, including cucumbers, are affected by white rot. The latter is a flaky white coating with black dots located inside. With the development of this disease, the plant tissues soften, mucilage occurs, after which the cucumbers wither and their fruits die. The risk of developing root rot exists regardless of the stage of plant growth.
In most cases, the disease makes itself felt when the plant enters the fruiting phase. Based on what signs can this be established?
First of all, the lower part of the stem near the roots becomes covered with brown spots, which merge over time; the plant tissue itself acquires a brown tint, which begins to rot, after which the rot spreads to the roots. As a result, the plant begins to receive less water and nutrients.
This also explains the yellowing of the upper leaves (this is accompanied by the acquisition of green veins). Wilting of the leaves of the plant is observed before or during fruiting.
With sudden changes in temperature during the day and night, rot causes maximum damage to the plant. The best method to effectively resist cucumber diseases is regular preventive measures. As is known, the costs of disease prevention are not comparable with the costs required to treat plants.
The main activities include preparing seeds, preparing soil, cultivation structures, and agricultural equipment for each summer season. For example, in order to eliminate the risk of root rot affecting the cucumber crop, it is recommended to sow benign, treated, hardened seeds. At the same time, one should not deviate from the agricultural technology of growing cucumber crops.
There are summer residents who, due to insufficient experience, choose narrow and high beds for planting crops, from which irrigation water drains quite quickly. Because of this, the leaves on cucumbers and stems wither and, ultimately, this leads to the death of plants caused by physiological wilting.
How to spray cucumbers if the leaves wither
However, not everything is so hopeless. It is necessary to prepare an intense pink solution from ordinary potassium permanganate. Use it for spraying, while providing the plants with plenty of watering, carrying out regular hilling.
A good effect is obtained by treating the lower part of the stems with the preparation “Kornevin”, “Gitrauxin”, which have a stimulating effect and promote the formation of new roots. Often, hilling will promote the formation of adventitious roots.
This will bring the plant back to life and expect a harvest. There is an alternative - biological preparations “Fitosporin” and “Trichodermin”.
The actions here are similar to those described above. Along with this, wilting of cucumbers can also be caused by a sudden change in weather, even in the absence of frost. Cucumber belongs to the southern crops and has a weak root system.
Weak root hairs are unable to withstand low soil temperatures, which causes the plant to wither. When planting a plant directly in open ground, there is a risk of its death in case of cold weather. Therefore, it is worth taking care of shelter for cucumbers. Having listed the main reasons why cucumbers turn yellow in a greenhouse, we will consider each of the listed problems in more detail.
Violation of agrotechnical conditions
Low temperatures and frosts
Cucumber, as you know, is a warm and moisture-loving plant. In the middle zone, especially at the end of May, so-called "return frosts".
Cucumber seedlings planted under film covers or in greenhouses may not only turn yellow, but also stop growing and developing. To avoid cucumber leaves turning yellow in the greenhouse, it is necessary to additionally cover the planted plants with lutrasil or bubble wrap.
Many gardeners, in sub-zero temperatures and frosts, place plastic bottles with hot water under such shelter in order to maintain a normal temperature for the growth and development of cucumbers. Attention: It is important to remember that this plant prefers a temperature within +22+260C for its development. If the temperature drops below +140C, or above +420C, the plant stops its growth and development.
If the temperature is below -10C, the cucumber seedlings will die. Thus, in order to protect cucumbers planted in a greenhouse from frost and low temperatures, they should be additionally covered with a film placed on the arcs or with a special non-woven covering material such as lutrasil, agrotex or spandbond. This is what will help maintain an acceptable temperature for plants in the greenhouse.
Lack of mineral elements in the soil
Also, the reason why cucumber leaves turn yellow in a greenhouse may be a lack of minerals in the soil in which the plants were planted. As a rule, the leaves of cucumbers in a greenhouse turn yellow due to a lack of nitrogen.
Yellowing begins with the leaves having a lighter color, and then completely turning yellow, both the veins themselves and the entire space of the leaf between them. Subsequently, all the vines of the plant turn yellow.
Another sign indicating a nitrogen deficiency in the soil is the irregular, “hook-shaped” shape of the fruit. A lack of nitrogen in cucumbers can be caused by excessive application of wood ash, potash fertilizers or superphosphate.
In order to avoid nitrogen deficiency in cucumbers, it is recommended that cucumber seedlings, a few days before planting in greenhouses, be fed with fertilizers and sprayed with a solution of microelements (see How to choose the right fertilizer for cucumbers in a greenhouse). When digging up a greenhouse in autumn and spring, it is necessary to add add rotted manure at the rate of two to three buckets per 1 m2. This will help avoid nitrogen starvation in plants.
If manure was not introduced during the digging process, then before planting the seedlings in the greenhouse, you can add rotted mullein to the soil, and throughout the growing season, feed the plants with an aqueous solution of mullein or chicken droppings, as well as an infusion of herbs, which is also called “herbal tea." The application of mineral fertilizers containing nitrogen will also help eliminate the lack of nitrogen in the soil.
The leaves of cucumbers turn yellow in greenhouses and greenhouses even when too much mineral fertilizer is added to the soil. Before applying any fertilizer, carefully read the manufacturer's instructions on the package.
Insufficient watering
Cucumbers are moisture-loving plants and require both frequent watering and high humidity in the greenhouse or greenhouse where they are grown. However, watering these plants should be done only with warm and settled water.
Cucumber leaves turn yellow in a greenhouse both from watering with cold water and from insufficient water. At a time when active fruiting occurs, watering should be increased.
It is necessary to moisten the soil quite deeply, since it is the deep penetration of water that will contribute to the development of not only the surface, but also the deeper root system of plants. Irregular and insufficient watering will affect both the leaves themselves and the ovary and fruits of cucumbers.
Poor pollination
One of the reasons why cucumber ovaries turn yellow in a greenhouse may be poor pollination of flowering plants. This can happen due to the fact that only artificially pollinated plants were planted, as well as due to the lack of ventilation or access for insects to pollinate the plants (see How to attract bees to grow a good harvest).
In this case, you can use spraying with boric acid dissolved in water (5 grams per 10 liters of water), or drugs "Bud" or "Ovary". Natural methods include spraying with sweet water (one tablespoon of sand or honey dissolves in two liters of water), which will attract insects.
Next season, in the greenhouse in which you plan to plant cucumbers, plant dill or some honey plants, for example, borage, hyssop. These plants will be able to attract insects to the greenhouse, which will be able to pollinate the plants and promote the formation of normal ovaries.
Plant overload with ovaries
In the literature devoted to gardening and growing cucumbers in greenhouses, when asked why cucumbers turn yellow in a greenhouse, they answer that it is not advisable to leave more than 20-25 ovaries on one plant at a time. This is due to the fact that cucumbers develop quite quickly in greenhouse conditions. In many hybrid varieties, it is possible to form more than one hundred and fifty ovaries on one plant at a time.
It is necessary to pinch out new shoots in a timely manner to allow cucumbers to form and ripen normally. If excess shoots and ovaries have not been removed, the fruits may develop an unattractive shape, and cucumbers in the greenhouse may turn yellow.
Damage to plants by insects or fungal infections
So, let's figure out what insects and diseases can harm cucumbers, and how to deal with them (see Diseases of cucumbers in a greenhouse, causes and methods of treatment).
Fungal diseases
Fusarium wilt or fusarium is a fungal disease
This disease manifests itself as follows: cucumbers sprout normally and grow well, but as soon as the ovaries begin to appear, the leaves of the cucumbers in the greenhouse first turn yellow, after which the vines dry out. The fungus that causes this disease penetrates the plant and releases toxins that limit the supply of nutrients and trace elements to the leaves and stems.
The way to combat such fungal infection is to regularly change the varieties planted in the greenhouse, as well as partially replace the affected soil. Powdery mildew is also a fungal disease.
In this disease, the fungus blocks photosynthesis processes in the plant. First of all, small light spots appear on cucumber leaves, which gradually spread to the entire surface of the leaf.
On all leaves of the plant, a whitish or reddish coating is observed on the upper surface of the leaf blade. After which the leaves of the cucumbers in the greenhouse turn yellow and dry out. To prevent the disease from visiting your greenhouse next season, you need to take a number of measures. First of all, when choosing cucumber varieties for the next season, pay attention to the resistance of a particular variety to powdery mildew, and also annually treat the soil in the greenhouse with potassium permanganate or green manure.
Downy mildew (pernosporosis)
The appearance of such a disease in greenhouses is facilitated by very densely planted plants, as well as excessive humidification of the air and soil in the greenhouse. The first signs of the development of downy mildew are the appearance of yellow and light spots on the leaves, which are limited by the veins.
Subsequently, the spots become oily and light yellow, and eventually turn brown. On the underside of the leaf blade, in those places where there are spots, a grayish-brown coating forms. If no measures are taken, the plant will die within a few days.
If cucumbers in a greenhouse turn yellow, root rot may also be the cause of this phenomenon. Plants at any stage of development can suffer from this disease.
The reason for such damage to cucumbers can be a significant difference in night and day temperatures, as well as watering the plants with cold and unsettled water. Weakened plants are the first to be affected, and then other plants become infected through the soil. In order to prevent plants from being affected by this disease, it is necessary to treat the root area with Previkur twice per season, according to the instructions.
Pests
melon aphid
This pest prefers to “infest” the underside of cucumber leaves and feeds on plant sap, which is why cucumbers turn yellow in greenhouses. The melon aphid poses a threat to cucumbers throughout the summer season.
Spider mite
This pest appears primarily on the inside of the cucumber leaf, where it weaves small webs. First, white or light yellow spots appear on the leaf, and then the leaves become completely covered with yellow spots and dry out. Throughout the warm days, spider mites multiply and if you do not fight them, for example, with the preparations “Akarin”, “Tsimbush”, “Fitoverm” and others, then you can lose all the plants in the greenhouse.
Cucumbers are grown by almost all gardeners, both experienced and beginners. The technology for growing this crop is known to everyone, but nevertheless, in many areas every season a problem arises - the leaves of cucumbers wither.
Let's try to figure out why this happens. The first and most common reason why cucumber leaves wither is a simple lack of moisture. If a plant does not have enough water, its leaves will first droop, wither, and then begin to dry from the edges to the center.
How to determine that the cause is a lack of water? It’s very simple - start moistening the beds every day, morning and evening, and if the situation quickly changes for the better, then the problem was only in the wrong watering regime. The second reason why cucumber leaves wither is directly related to the first.
If you planted tomatoes and cucumbers in the same greenhouse, such proximity will not lead to anything good. Despite the fact that both plants are heat-loving, cucumbers require high air humidity, which tomatoes cannot tolerate at all.
That’s why it may turn out that, trying to please the tomatoes, you “dried out” the cucumbers, and they again suffer from a lack of water. The third reason why cucumber leaves wither is when herbicides get into the garden bed. Cucumbers cannot tolerate them at all, so you should not use chemicals not only in the greenhouse, but also in neighboring beds.
If the herbicides have already managed to reach the plants, then abundant watering will help - the chemicals will simply be washed off with water and go further into the soil. Another reason why cucumber leaves wither is damage to aphids. It is very easy to confirm or refute this - you need to look at the back of the sheet.
If you find aphids there, then you need to take urgent measures, since the pest can infect all healthy plants in a matter of days. It is best to use a soap solution or special chemicals, such as Iskra or other similar preparations.
In addition, cucumbers may suffer from fungal disease or mites. The first is eliminated using chemicals such as “Photosporin”, and the second is eliminated by using an infusion of onion peels. The last reason why cucumber leaves wither is incorrect agricultural technology, that is, a whole complex of factors that affect the plant to one degree or another.
For example, excess or lack of fertilizer, incorrectly chosen planting location, when direct sunlight actually burns the leaves. This can also include incorrect watering technology, when plants are watered often, but little by little.
As a result, water does not reach the roots, and the plant begins to suffer. Another watering mistake is spraying water directly onto the leaves on a bright sunny day.
Droplets of water turn into tiny lenses and the cucumbers get burned. So, we have enlightened you on the question of why cucumber leaves wither and indicated the most effective methods of combating this phenomenon. Take care of your plants, and they will delight you with a tasty and rich harvest.
The first thing, of course, is to find out why this happens, that is, your task is to correctly determine the reason. She may not be alone at all, so we need to figure this out. Cucumbers can still be classified as delicate plants; they are very sensitive to changes in the conditions that we create for them when growing them. Also, the weather can significantly influence this process. It happens that yesterday you were in the garden, your cucumbers were in perfect order, that is, they looked great, grew well and even began to form ovaries. Today, the picture no longer pleases you. The leaves of the cucumbers are drooping, looking into them, and at the same time have already seriously withered. What happened to them?
The main reasons for leaf wilting in cucumbers
And there are plenty of such reasons. They all seem quite simple. So study them carefully, compare them with the conditions in your garden, and I’m sure you will immediately understand what can be done to save your cucumbers.
Read also: Indoor cucumbers: growing in winter
Not enough moisture
If the leaves wither on any plant, not just cucumbers, then this reason immediately comes to mind. Yes, it most often causes leaves to wilt, because cucumbers love to be watered promptly and abundantly. If you pour little water on them, the soil may dry out, and following this phenomenon, the leaves will begin to wither. Here, immediately grab the watering can and pour more water onto the beds. If you delay watering, the wilted leaves will simply turn yellow and die. Further, it simply shouldn’t come to this. Cucumbers must be watered 4 or 5 times a week.
Few nutrients
This also often leads to such leaf wilting. After all, their mass in cucumbers is quite large, and it needs to be constantly “fed”. Often the lack of the required amount of nitrogen leads to this result. If the cucumbers have enough moisture, but not enough nitrogen, then it must be added on time.
Liquid chicken manure helps very well in this case. In addition to droppings, urea is also suitable, which only requires a tablespoon. For the usual amount of water, that is, 10 liters. The foliar type of fertilizing with urea quickly gives good results, and your cucumbers will turn green again.
Lots of direct sun
When the sun gets too hot, the leaves often can’t stand it. Cucumbers do especially poorly when the sun shines directly on them all day. At the same time, the leaves wither quite quickly, then they turn yellow, and it is no longer possible to expect a decent harvest from such a plant.
All plants were once wild. If we talk about cucumbers, in nature they always grow under some kind of trees. They slowly “climb” onto them, simply wrapping around their trunks. You just need to put this into practice when you choose a place for them. The vines of cucumbers can simply be covered, that is, shaded. To do this, you can use covering material.
Leaves wither due to pests or diseases
In cucumbers, some diseases can lead to exactly this result. This is the same powdery mildew (more about it and other diseases here), as well as cladosporiosis or olive spot.
Of course, all these diseases can be prevented; this is quite possible to do. Potassium permanganate along with a chalk solution will help you with this. Just spray the cucumbers, and those leaves that are already severely affected must be torn off.
The melon aphid is also dangerous. Garlic infusion will help you defeat it. You can make it even simpler, plant cucumbers next to the garlic beds, then aphids are not scary for them.
All of these were the most common causes of leaf wilting on cucumbers. Keep an eye on your cucumbers and deal with them on time, then your cucumbers will feel good, which means that you will have a harvest. But here is also a useful video for you, where they will tell you about cucumbers. How to protect them from root rot, which can also be the reason why their leaves wither.
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