Gardeners growing cucumbers in greenhouses periodically encounter the fact that the leaves of plants turn yellow. The reasons for this phenomenon are different: from violation of growing conditions to diseases of cucumbers. Let's think about what to do if the cucumber leaves in the greenhouse turn yellow.
Violation of agricultural technology for growing cucumbers
Everyone knows that cucumbers are very fond of moisture and warmth. However, return cold often occurs in spring, when the temperature in the greenhouse can drop below the permissible + 14 ° C. At the same time, cucumber seedlings may turn yellow and their growth will stop, and at temperatures below 0 ° C, they may even die.
To help cucumbers survive such spring colds, it is necessary to make additional shelters over the plantings using special covering materials or a regular film.
Another reason that the leaves of cucumbers in the greenhouse turn yellow may be a lack of minerals in the soil, in particular nitrogen. At the same time, the leaves turn yellow first, and then the lashes, and the fruits themselves become hook-shaped. To prevent this, seedlings, before planting them in a greenhouse, should be fed with fertilizer with the necessary trace elements.
Yellowing of cucumbers is caused by insufficient watering. If cold water is used to moisten the soil under cucumbers, then the plants do not like it, and they will turn yellow. Therefore, it is necessary to regularly water the cucumbers in the greenhouse with warm and preferably settled water.
Diseases of cucumbers, in which the leaves turn yellow
Often, cucumbers are affected by a fungal disease such as fusarium. At the same time, during the appearance of the ovaries, the leaves first turn yellow, and later the lashes of the plants themselves dry out. Powdery mildew is also a fungal disease in which the leaves of cucumbers turn yellow in spots. So that these diseases do not affect greenhouse plantings of cucumbers, it is necessary to cultivate the soil before planting with potassium permanganate or use green manure, and in addition, choose varieties of cucumbers that are resistant to these diseases.
Cucumbers can be affected by aphids and spider mites throughout the season. It is recommended to fight them with such drugs as Akarin, Tsimbush, Fitoverm, etc.
womanadvice.ru
The first answer to the question: “why do cucumber leaves turn yellow?” there will be a lack of moisture. Everyone needs water, and especially fruit plants, which, when there is a shortage of water, begin to save it and drop their leaves for this, and before the leaf falls, it turns yellow due to the fact that the plant begins to draw magnesium from the leaf and redirect it to the stem and roots.
Many summer residents make mistakes when watering cucumbers.
- or watered often and little, believing that this way the plants get moisture better. But in fact, with small and frequent watering, moisture does not reach the roots in depth, but is distributed in the soil. The plant begins to adapt, and the roots rise higher, where they overheat in strong sun and are also damaged when loosened;
- or watered a lot, but rarely. It turns out: at some point the culture is flooded with water, but during a hot summer, the water quickly leaves and as a result, the plant does not receive the necessary moisture, or the roots begin to rot.
It is very important to correctly organize the watering of cucumbers so that the fruits are undeformed and tasty, and the leaves are green. The norm for watering cucumbers is about 25 liters per plant with two waterings per week.
You also need to test the soil for moisture, periodically take a piece of earth from a ten-centimeter depth and squeeze it in your hand, determining whether the earth is wet or not, in order to avoid overfilling or underfilling.
Of the diseases that cause the yellowness of the leaves of cucumbers, first of all, fungal diseases should be pointed out. They develop strongly when crop rotation is not respected. Fungi and pathogens accumulate in the soil.
Cucumber protection
So, choosing the right planting site, timely deep watering of cucumbers and feeding them will largely ensure the well-being of plants. When fertilizing, be careful about dosages.
To curb the development of fungal diseases, crop rotation is necessary, in which pumpkin crops are planted on the previous beds no earlier than four seasons. In greenhouses, it is recommended to periodically replace the soil or carry out disinfection.
In addition, biological methods of soil disinfection are used, in which the soil is carefully removed from the greenhouse and placed outside in a stack no more than a meter high. Each layer is spilled with biologically active microorganisms (Baikal EM-1 preparations, humus tinctures, etc.), compost can be added. Such disinfection takes 2-3 years.
Remember that the spread of fungal diseases is facilitated by mechanical damage to the roots and trunks of cucumbers. Since their roots are very susceptible to damage, it may be best to do without loosening the soil. In this case, pay more attention to soil preparation before planting.
In addition to the alternation of vegetable crops, biofungicides containing trichodermin can be recommended for the biological protection of cucumbers. It is necessary to introduce mycelium into each hole at a distance of 3-10 cm from the shoots. Trichodermin inhibits the development of pathogens and has a stimulating effect on the development of vegetable crops. Not phytotoxic, harmless to insects, humans and animals.
The yellowness of the leaves is best prevented by observing the growing conditions and providing the cucumbers with the necessary nutrients. In addition, it is necessary to monitor the state of the microflora of greenhouses and the site, to prevent the development of pathogenic fungal diseases. Then you will always have healthy plants and a high yield of cucumbers.
OgorodSadovod.com
Why do cucumbers turn yellow in a greenhouse? | Questions and Answers – www.FAQL.ru
Appeared more than 6 thousand years ago, the cucumber is still one of the favorite crops of gardeners. This fruit not only tastes good, but also has a wide range of medicinal and dietary properties. Cucumbers are easily digested by the body, regulate bowel function and remove excess cholesterol. And due to the presence of potassium, they improve the functioning of the heart and kidneys.
Cucumbers are grown in almost every garden. However, they require special care, and if something is not observed, they begin to turn yellow. Therefore, today in our article we will tell you why cucumbers turn yellow in a greenhouse and what needs to be done to avoid this.
Why do cucumber leaves turn yellow?
Diseases and insects are two reasons why cucumber leaves turn yellow. Diseases are the result of non-observance of optimal conditions for growing cucumbers. To avoid them, it is necessary to properly water and fertilize the plants, to avoid temperature changes. For prevention, the root area should be treated with fungicidal preparations according to the instructions.
One of the main reasons why cucumbers turn yellow in a greenhouse is irregular watering and use cold water. If you want your cucumbers to grow healthy, water them properly.
It is important that the cucumber soil is always moist, but in no case turn it into slush. Water for irrigation should be settled and heated in the sun. In the heat, watering should be daily, in the evening, followed by careful loosening of the soil. If cold weather is planned at night, then watering should be done in the morning.
How to properly feed cucumbers?
At the beginning of the growing season, the cucumber needs more nitrogen, during the period of growth in a loop - potassium, during fruiting and the appearance of new growths, nitrogen is again required. Therefore, improper feeding can be another reason why cucumbers turn yellow in a greenhouse. The main thing to remember is that plants need little, but proper feeding.
Cucumbers have weak roots that are not able to penetrate deeper than 20 cm, so the plants are especially sensitive to the properties of the soil. Fertilize it with manure, decayed garbage, straw, peat or sawdust. Enrich the compost with nitrogen and fertilize locally. Do not forget about mineral fertilizers.
Over the summer, you need to properly feed cucumbers no more than 5 times. The first feeding is carried out at the beginning of flowering. The next four are during the fruiting period. They use chicken manure and mullein, but they can also be replaced with ready-made top dressings.
When warming comes to replace a long cold snap, greenhouse cucumbers need ammonium nitrate. Cucumbers are fed by placing fertilizer in the furrows, after which they are watered. During low temperatures, the plant is supported by foliar top dressing.
Cucumbers love warmth.
When choosing a place for planting cucumbers, you need to be guided by such a factor as the absence of a draft. Since a draft and sudden changes in temperature can be the reason why the leaves of cucumbers turn yellow.
The greenhouse can only be opened when the temperature inside exceeds 30°C. Moreover, you need to open the doors on each side in turn. Opening from both sides at once, you will allow the appearance of a draft.
How to get rid of pests on cucumbers?
There are a lot of insect pests, as a result of which cucumbers turn yellow in the greenhouse. This is a sprout fly, and a cucumber mosquito, and aphids, and a spider mite. All these insects or their larvae feed on the leaves, stems and fruits of cucumbers, which inevitably leads to drying and death of the plant.
To get rid of them and save the plant and crop, you need to choose the right pest control agent. But do not forget - after treating the plant with one or another drug, all grown fruits must be removed and discarded. It is extremely unsafe to eat cucumbers that have been contaminated with drops of pest control agents.
faql.ru
Cucumber leaves turn yellow, why and how to fight. What to do when the leaves of cucumbers in the greenhouse turn yellow
Why do cucumber leaves turn yellow in the open field
- Irrigation violation. One of the main reasons that can lead to yellowing, drying and subsequent death of greens on cucumbers. Sometimes vegetable growers forget that the culture is moisture-loving and requires more water on especially hot days. Although, here it is also important not to overdo it and carry out water procedures not occasionally, but in excess, but regularly and in sufficient quantities. It is best to do this 3-4 times a week, making sure that the root system is not exposed during watering, and moisture droplets do not fall on the leaves and do not provoke potential sunburn.
- Wrong lighting. Cucumbers prefer bright places, protected from direct sunlight by a diffused shadow. Once in the center of the garden, they turn yellow and dry out in just a few days, unable to withstand such a harsh test of heat. But in cozy, slightly shaded areas, the plants feel comfortable and delight the owner, first with bright foliage, and later with a plentiful harvest of beautiful, regular-shaped fruits.
- Lack of complete nutrition. A lack of nitrogen in the soil very often leads to yellowing of the edges of cucumber foliage. To avoid this unpleasant moment, it is necessary to carefully prepare the soil before planting seedlings and bring it into the ground. a large number of humus and rotted manure. When the plants enter the active growth phase, you will need to regularly feed them with a special nitrogen-containing fertilizer. But here it is extremely important to strictly follow the manufacturer's instructions and not abuse the top dressing, since with an excess of nitrogen it has the unpleasant property of decomposing into nitrates.
Cucumber leaves turn yellow in the greenhouse - what to do?
Moisture and heat are two conditions that ensure the full growth and maturation of a good crop of cucumbers. However, some gardeners sometimes believe that it is enough to build a greenhouse and a favorable environment inside will develop on its own. This is an erroneous opinion, which in almost all cases leads, if not to the complete death of plantings, then to a significant decrease in the level of fruiting. And plants protected by polycarbonate, glass or polyethylene walls still get sick, suffer from a lack of nutrients in the soil and need constant careful care. Even in the most luxurious greenhouse, cucumber leaves often turn yellow, the edges dry up and the ovaries die. In addition to diseases and pests, this phenomenon is caused by violations of the agrotechnical principles of growing vegetable crops, for example, uncomfortable indoor temperatures resulting from unexpected return frosts.
What to do in this case? Of course, to insulate and create additional shelters on top of the greenhouses from modern and practical protective materials or from ordinary plastic film. The average temperature in the greenhouse should not fall below +14°C. Only under such conditions will seedlings survive the spring cold snap and retain green, attractive foliage.
Watering during this period of time should be given special attention. The use of cold running water is strictly prohibited. Cucumbers do not tolerate it very well and may well express their “displeasure” with the massive yellowing of the foliage.
Diseases of cucumbers, in which the leaves turn yellow and dry
Among cucumber diseases, there are several that cause, in addition to other symptoms, active yellowing and drying of leaves, stems, and subsequently fruits. The most unpleasant of them are:
Sometimes it is very difficult to determine both by eye and by photo why the leaves of cucumbers turn yellow in a greenhouse or in open beds. It seems that the watering is timely, and the direct rays of the sun do not fall, and the temperature regime is suitable, and pathogens on the plants are not noticed. And yet, despite this, the lower leaves along the edges rust and dry literally before our eyes. What to do in this situation and how to deal with an unpleasant symptom, the author of the video tells.
otvetkak.ru
Why do cucumber leaves turn yellow?
VC
Nadias
If the leaves of cucumbers begin to turn yellow around the edges, then there may be several reasons for this, because it is the green color of the leaves that is considered normal. The most obvious reason is that the plant lacks trace elements, and if yellowing occurs from the edges, then the reason is not enough potassium in cucumbers. If the whole leaf turns yellow, then the plant lacks magnesium.
What to do in this case - all gardeners will ask this question. Well, of course, the soil must be fertilized, "feed". But even with fertilizer you should not overdo it, you need to know when to stop. It happens that cucumbers lack moisture, water, in this case it is necessary to water the plant abundantly with settled water warmed under the rays of the sun.
nastyastar
Cucumbers are not long-lived plants, but, nevertheless, I would not like to observe yellowed leaves on young plants.
Leaves may turn yellow due to prolonged rainy weather or excessive flooding with water. This usually happens during the seedling stage.
The other most common cause is a lack of nitrogen, less commonly potassium.
In order to avoid such a problem, it is recommended to plant cucumbers on a bed well seasoned with manure. Also, once a month, you can feed cucumbers with purchased mineral fertilizers. Once a week, you need to pour a weak solution with fertilizer under the bushes.
Lilka-g
In general, all plants that are green are due to the fact that they contain Chlorophyll.
If in a Plant, for example, in a cucumber, the edges of the leaves begin to turn yellow, this tells us that there is no Chlorophyll in these parts.
And why exactly yellow?
Because cucumbers lack potassium.
If you water your cucumbers well, then everything will be fine.
I think I was able to help you with the answer.
I wish you a lot of cucumbers and health)
Online
You are probably not watering them properly. If cucumbers are often watered, but with a small amount of water, then water and nutrients will not reach the root system of cucumbers and the leaves will immediately let you know about it. It is possible to overflow the plants with water, and in this case the leaves will turn yellow, because then, from excessive moisture, the roots begin to rot. Do not water at the peak of solar activity, water in the morning or evening. Fertilize in the correct dosage so as not to burn the plants with urea. Well, do not allow the formation of any fungi in the soil.
Right here
The first thing you should pay attention to is how abundantly cucumbers are subject to watering, that is, how much moisture they have to eat. That is, if there is little moisture, then it will be obvious that the leaves will turn yellow, so it is imperative to monitor watering and water access.
But there are also many other reasons that can affect the fact that the leaves begin to turn yellow, here is the following list, where you can find a lot of useful information so that the cucumbers turn out just healthy and tasty:
Solnce lychik
Maybe cucumbers just lack moisture? After all, all cucumbers love water.
Cucumbers need to be watered properly. They need to be filled with water so that water penetrates into the deep layers of the earth and the roots of cucumbers absorb moisture.
But watering does not need to be carried out too often. It will be enough to pour cucumbers with water 2-3 times a week. If you water too often, the roots will rot. It will be just as bad.
Make sure that water droplets do not fall on the leaves, otherwise the leaves may be burned.
Elena D
The reasons for the discoloration of the leaves of cucumbers can be different. Most often, the problem is associated with a lack (or, conversely, an overabundance) of nutrients, microelements. Here it will be important to pay attention to the nature of yellowing - the measures taken will depend on this.
More information can be found here. There is also a good article here.
Roxrite
There may be several main reasons at once: this is a lack of moisture in the soil, infertile soil, the wrong location of the beds (ideally, when a shadow falls on the cucumbers in the middle of the day), then sunburn can be avoided.
Measures to help you avoid yellowing of the edges of the leaves of cucumbers:
Annet007
The edges of cucumber leaves can turn yellow for several reasons. And this:
- small watering (if you notice this, then first of all you need to increase it)
- Prolonged exposure of leaves to the sun (it has already been proven by experience that the sun "burns" the leaves, they turn yellow and dry out)
- Potassium deficiency / pests / infertile soil
Leona-100
The leaves of cucumbers can turn yellow from insufficient or vice versa excessive watering, from a lack of minerals in the soil. Also, cucumbers should not grow in bright sun, they need shade. The soil must be properly fertilized and treated with cucumbers from pests.
FerdinandRUS
lack of substances and usually appear when there is a lack of water, as well as when watering in the "hot" sun
Today, almost every gardener is engaged in growing cucumbers. And this is not surprising, because cucumbers are a fairly common vegetable crop. Its fruits can be consumed both fresh and canned. But you need to understand that, like any culture, careful care is needed for cucumbers. Yellow leaves are one of the most common problems. To fight this scourge, you must first understand what led to its development.
The best treatment is timely prevention. To do this, you must follow a number of simple rules and apply time-tested folk remedies.
Before proceeding to the preparation of home solutions, it is necessary to consider the basic recommendations for caring for the culture, which help prevent yellowing of the leaves:
And here is how tomato seedlings are fed with yeast and ash, it is indicated
On the video - what to do when the leaves on cucumbers turn yellow:
So that the leaves on the bushes do not turn yellow, you can process them using the following tools:
And here is how cucumbers with corn are planted in open ground, and how planting materials, set out in this
How to deal with late blight on cucumbers
Late blight is a common disease, the development of which is affected by fungi. Cucumbers grown in open field and greenhouse. The peculiarity of the disease is that its pathogens are quite tenacious and can be in the ground for a long time. This is especially true for those soils where there is a shortage of copper salts.
Most often, late blight occurs in cucumbers growing under a film coating. Condensation forms due to sudden temperature drops day and night. Excess moisture forms on the surface of plants. You can see the first symptoms of late blight on potatoes, and after 9-10 days cucumbers are affected.
On the video - how to deal with late blight on cucumbers:
To combat this disease effectively use the following proven tools:
Caring for cucumbers is actually quite easy. Even an inexperienced gardener can cope with everything. One of the important aspects of care remains the fight against pests and ailments. It is they who lead to the development of such symptoms as yellowed leaves. To eliminate this problem, you can use both purchased drugs and proven folk remedies.
Prematurely yellowed leaves in cucumbers are a problem that signals a plant disease, which will certainly affect its yield. To avoid the death of the plant and maintain a high yield, you must first understand why exactly the leaves of cucumbers turn yellow. And there may be several reasons for such an unsightly phenomenon. The most common of them, as well as what to do if the cucumber leaves turn yellow, will be discussed further.
Why cucumber leaves turn yellow - the main reasons
Experts identify several main reasons that can provoke yellowing of cucumber tops. One of the most common is improper watering. Moreover, it can be, as well as a lack of moisture, and its excess. So, too little water leads to drying and yellowing of the leaves. And abundant watering erodes the root system, the roots of cucumbers rise to the surface where they are exposed to aggressive external factors, for example, direct sunlight. In addition, the leaves of cucumbers turn yellow even if cold water falls on their surface during irrigation on a hot sunny day and causes burns. Therefore, it is recommended to water cucumbers in the early morning or evening hours, when the sun is no longer so aggressive.
The next reason why the leaves of cucumbers turn yellow is also associated with the sun, or rather, with its lack. If the lower part of the tops in the middle of the garden is yellowed, then most likely this is due to the banal death of the leaves due to lack of light. This process is absolutely natural and does not require any action on the part of the gardener. But if the leaves of cucumbers are covered with yellow spots resembling rust, then this is already a reason to sound the alarm. As a rule, this is a sign that the cucumbers have been affected by a fungal infection, such as pitiosis or fusarium. In this case, the leaves will quickly turn yellow and dry, and then fall off.
Cucumber leaves may also turn yellow due to insect pests. For example, a spider mite sucks out all the juices from a plant, which first leads to yellowing of the tops, and then to the death of the plant. Also, the condition and color of the tops is strongly affected by the lack of minerals in the soil, the lack of timely feeding. For example, a lack of potassium and magnesium is reflected in the yellowing of the leaf edge.
Cucumber leaves turned yellow - What to do
Now let's figure out what to do if the cucumber leaves turn yellow and dry. First of all, you need to establish the root cause, and then deal with its manifestations. For example, normalize watering if the yellow leaves are the result of its lack. It is also important to consider the place where plants grow. For example, cucumber leaves in a greenhouse often turn yellow and dry due to improper air exchange and disturbed temperature conditions. In this case, it is important to ventilate the greenhouse as often as possible, while avoiding sudden changes in temperature.
In addition, the correct crop rotation must be observed. In other words, do not plant cucumbers in the same place year after year, as this encourages the accumulation of fungi in the soil. Also, you can not plant cucumbers in places where other pumpkin crops, such as zucchini, used to grow. Ideally, replanting cucumbers in the previous area is possible no earlier than after 4 seasons.
How to feed cucumbers if their leaves turn yellow and dry
If the causes of yellow cucumber leaves lie in the lack of minerals in the soil, they must be “feeded”. To do this, you can use both specialized top dressing and folk remedies. Preference should be given to organic and mineral fertilizers. In this case, the choice of feeding should depend on the lack of a particular mineral. For example, without potassium and magnesium, the edges of the sheet begin to turn yellow and dry. If only the upper leaves turn yellow, then this indicates a lack of copper. But the green veins against the background of a yellow leaf signal an iron deficiency. You can find out how to feed cucumbers if their leaves turn yellow and dry from the video below.
How to water cucumbers so that the leaves do not turn yellow: folk remedies
In addition, there are a number folk remedies, which help fight yellowed cucumber tops. The simplest and effective method- water cucumbers with herbal infusion with ashes. Most often, for these purposes, a collection of several herbs is used: nettle, horsetail, chamomile, tansy. To prepare the infusion, you can use both fresh leaves of these plants and dry herbs. Chopped herbs should be poured into a non-metallic container and filled with 3/4 warm water, covered with a lid and left for 3-4 days in the sun for fermentation. Ready infusion for irrigation should be diluted with water in a ratio of 1: 9 and add wood ash.
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Yellowing of seedlings, ovaries and leaves of cucumbers can often be observed when growing these plants. Especially if the weather isn't great...
1:747 1:756Cucumbers turn yellow for many reasons. Perhaps this is a lesion with peronosporosis or a lack of moisture. Or it could be the other way around - excess water, lack of nutrients or too cold nights. Often this happens due to the activity of ticks. Read our article on how to save cucumbers from yellowing.
What is the matter and how to be?
There can be many reasons, so we will consider them from simple to complex.
IMPORTANT: Cucumbers love when it's warm, light and damp!
Cold nights.
Cucumbers really don't like it when it's cold at night. The optimal night temperature is 19-22 gr. at 12-15 gr. cucumbers start to hurt.
Lack of water and air humidity.
Cucumbers are very demanding on soil and air humidity, the optimum air humidity is 75-85%, soil 700-80%. This is due to the fact that the leaves of cucumbers evaporate a lot of moisture, and the roots of cucumbers lie almost on the surface.
Therefore, if watering is scarce or uneven, the plant begins to shed its leaves to reduce water evaporation.
We correct the situation by proper watering of cucumbers.
But you also need to know that excessive humidity, especially in combination with low temperatures, leads to fungal diseases. So don't overdo it!
Sometimes we just pour over our cucumbers. And diseases begin .... It is especially necessary with watering when it is cold and damp outside.
How to determine if you need to water?
Test the ground with your finger. If the ground is warm and slightly damp, you can water. If it's cold and wet, don't. In general, this is a creative process ... Especially with our unpredictable weather.
Lack of minerals.
If everything is fine with watering, it is possible that the plants lack some microelements. Maybe just nitrogen. You need to feed.
No pollination.
The ovaries may turn yellow and fall off if they are not pollinated. For example, there are no bees. Carry out pollination by hand.
Roughly speaking, due to improper care, plants can weaken, wither and eventually die. To strengthen the immune system, it is not necessary to go to the store for stimulants. You can use hand tools.
1:420 1:429There are four ways to strengthen the immunity of cucumbers with safe folk remedies.
1. For 9 liters of water, take 1 liter of milk and add 30 drops of iodine. All this is flavored with 30 g of liquid soap. It must be added for the stickiness of the solution. The disadvantage of this method: in order to effectively deal with yellowness with such a solution, cucumbers must be sprayed once a week.
2. A cheaper and more realistic option - take 1 liter of whey for 5 liters of water.
Dilute the solution well and spray the foliage on both sides.
3. Boil a glass of onion peel for five minutes, then cover and leave to infuse for another 24 hours. Then strain the solution and add it to 5 liters of water. With this solution, spray the foliage on both sides, at the same time spray the soil, and pour the rest of the plants under the root. Treatments should be repeated every two weeks.
4. A slightly different option - 300 g of sugar is dissolved in 4 liters of whey and everything is diluted in a bucket up to 10 liters. All mix well and spray the plants. We hope everyone will choose the recipe to their liking and save the cucumber crop when it is no longer possible to spray plants with fungicides.
3:16483:8
Cucumber is a rather capricious culture, but not a single one gardener refuse to grow it. Pickles, marinades, salads, and preservation cannot do without cucumbers. Today's assortment of this vegetable is amazing.
And, nevertheless, every year the market is replenished with new, more productive varieties. Planting plants in greenhouses or soil, we hope to get an excellent harvest, but very often we are disappointed, watching how cucumber leaves turn yellow.Therefore, before starting to engage in this culture, you need to know in advance why?
The leaves of cucumber seedlings turn yellow what to do.
Vegetable growers have been growing cucumber seedlings at home for a long time and often encounter a change in plant pigmentation in the second leaf phase. The reason for this is not the soil used for seedlings, but an acute shortage of micro and macro elements. If the lower leaves turn yellow, cucumber seedlings need top dressing with phosphorus, magnesium, potassium. Yellowed upper leaves indicate a lack of iron, boron, manganese, zinc. Yellowness may appear due to a change in the ratio of trace elements in the soil, for example, potassium and ammonium salts.
Cucumbers overfed with nitrogen fertilizers get ammonia poisoning. "Elongated" seedlings indicate a lack of potassium. To organize the correct top dressing it is best to use ready-made, balanced microelement composition fertilizers for plants. An equally important problem is the correct formation of the cucumber root system, which is possible only in spacious pots. Do not miss the moment of picking, otherwise the seedlings you grow will be weakened.
If necessary, rearrange the cucumbers in a place illuminated by the sun or use artificial lighting. The most common mistake is improper watering. Do not keep cucumbers in dry or wet soil.
This is harmful to the root system! Cucumber culture is sensitive to temperature changes. Often yellowed and dry leaves are a response to cold nights. You will be surprised that the reason, why do cucumber leaves turn yellow, are foam plates on which seedlings are placed. Chemical compounds, penetrating into the soil, cause poisoning of plants, therefore, using polystyrene, it is better to wrap it with plastic wrap. Knowing all the possible causes of discoloration, you can independently decide when cucumber leaves turn yellow what to do.
Why do cucumber leaves turn yellow?
Yellowing of the leaves can be observed not only in seedlings. It is possible that fruit-bearing plants fell under return frosts.
Often the reason lies in the lack of watering plants or damage to the root system by pests. Frequent watering of plants in small portions does not allow water to penetrate deep into the soil. Occasional heavy watering is also useless.
Moisture remains in the upper layers of the soil or quickly seeps into the depths, without lingering in the soil. This leads to drying of the roots and yellowing of the leaves. It is enough if you start watering the cucumbers twice a week with warm water.
Avoid getting water droplets on plants, as they can cause sunburn of the leaves and change their pigmentation. Cucumber suffers from high temperatures, especially in greenhouses. The plant quickly ages and withers.
To avoid this, it is necessary to organize regular ventilation for fresh air. Quite often, cucumbers are affected powdery mildew . The lashes of plants are covered with a yellowish coating and stop growing.
As a result, cucumber leaves curl and turn yellow. Such plants are treated with Bordeaux mixture, Kuproksat, Acrobat and Bravo preparations. The key to a high yield is the correct crop rotation. It will be rational to grow cucumbers in one garden every four years.
In greenhouses, one cannot do without a complete replacement of the soil or its disinfection with Em-1, Baikal, humus tincture. Modern biological protection of cucumbers involves the use of biofungicides that inhibit the growth of pathogenic mushrooms . It is important, when working in the beds, to protect cucumbers from mechanical damage.
All sorts of injuries increase the possibility of infection or the spread of fungal diseases. When examining cucumber leaves, you should pay attention to the appearance of melon aphids or spider mites. When growing plants in a greenhouse, be prepared to fight back against the whitefly. Remember, Why do cucumber leaves turn yellow? with a deficiency of nitrogen, calcium, magnesium, copper, iron and zinc in the soil. It is better to prevent their yellowing and immediately provide the plants with the necessary nutrients.
Everyone knows that sometimes cucumbers in a greenhouse begin to turn yellow. What are the reasons for this? What can be done in order to get a crop? A scheme for planting cucumbers in a heated greenhouse. So, why do cucumbers turn yellow in a greenhouse?
There are three main reasons.
Cucumbers are moisture-loving plants, so they need to be watered regularly. To prevent cucumbers from turning yellow, use cold water for watering. Stand up for water. Increase watering during fruiting.
In addition, you need to moisten the ground well so that the roots of the cucumbers develop deep into, and not from above. If you don’t water the plants at least a few times, they will begin to turn yellow, and the new ovary will also turn yellow. The weather is often the reason why the plant turns yellow. Due to the cold and wet weather caused by frost, cucumbers are often damaged.
If the ovaries begin to rot, immediately remove the faded flowers and apply potassium permanganate to the cut. To prevent bacteriosis, spray - for this purpose, 1% Bordeaux liquid is used. If a yellow spot appears on the foliage, this indicates a lack of potassium, and light green indicates a magnesium deficiency.
Thus, cucumbers need to be fed. In addition, the development of the plant may be slightly disturbed due to the lack and scarcity of the soil. Make sure that there are no overdoses of fertilizer, because of which, as a rule, seedlings and their fruits turn yellow.
As soon as the cucumber seedlings are planted and after the harvest is completed, be sure to apply manure to the soil. And during the growing season, use complex mineral fertilizers (they should include phosphorus).
Fungal diseases and pests
A fairly well-known plant disease today is powdery mildew. If the leaves are covered with light spots, gradually increasing in size, then this indicates an infection. The leaves begin to dry and turn yellow.
How to eliminate this trouble? In this case, it is necessary to use fungicide preparations. There is another common cucumber disease - uzaria wilt. Because of this dangerous fungal disease, plants begin to die in the greenhouse.
Special preparations will help get rid of this pest. Root rot. Cucumber leaves turn yellow at the very bottom. This usually happens through significant temperature changes during the day or night.
The reason is the use of cold enough water for irrigation. The weakened plant is the first to fall ill, then the infection is transmitted through the earth to other crops.
Peronosporosis - the cause of the destruction of the crop
Table of diseases and pests of cucumbers. In addition, you need to talk about downy mildew (downy mildew). This disease, common in cucumbers, appears in a greenhouse with high humidity of air and soil. The affected fetus shrinks and turns yellow.
Often the entire crop is destroyed. How to understand that plants are sick? On the leaves (at the very bottom), green spots of an acute-angled shape may appear.
Means to eliminate peronosporosis will help cure the disease. Peronosporosis is the main disease of cucumbers in the greenhouse, in which the leaves begin to turn yellow. The plant is overloaded with ovaries. In a greenhouse, plants are able to develop quite quickly.
If you remove new shoots in a timely manner, you can prevent a delay in the development of greenery. But failure to comply with this rule may result in the appearance of underdeveloped, small and yellow fruits. In addition, sometimes fertilization is insufficient.
This happens when a hybrid variety is used in the greenhouse that requires artificial pollination. In the greenhouse, cucumbers turn yellow naturally when they are fully ripe, but only green fruits are used for food. These are the main reasons why plants turn yellow in greenhouses. By determining the cause, you can choose the best method for preserving the fruit.
Why do cucumbers turn yellow in a greenhouse?
Appeared more than 6 thousand years ago, the cucumber is still one of the favorite crops of gardeners. This fruit not only tastes good, but also has a wide range of medicinal and dietary properties.
Cucumbers are easily digested by the body, regulate bowel function and remove excess cholesterol. And thanks to the presence of potassium, they improve the functioning of the heart and kidneys. Cucumbers are grown in almost every garden.
However, they require special care, and if something is not observed, they begin to turn yellow. Therefore, today in our article we will tell you why cucumbers turn yellow in a greenhouse and what needs to be done to avoid this.
Why do cucumber leaves turn yellow?
Diseases and insects are two reasons why cucumber leaves turn yellow. Diseases are the result of non-observance of optimal conditions for growing cucumbers. To avoid them, it is necessary to properly water and fertilize the plants, to avoid temperature changes.
However, the "chemical" fruits collected during this period will have to be thrown away. With a sudden wilting of a plant, it must be completely removed, and with it the infected soil from the hole where it grew.
How to properly water cucumbers?
One of the main reasons why cucumbers turn yellow in a greenhouse is irregular watering and the use of cold water. If you want your cucumbers to grow healthy, water them properly. It is important that the cucumber soil is always moist, but never turn it into slush.
Water for irrigation should be settled and heated in the sun. In the heat, watering should be daily, in the evening, followed by careful loosening of the soil. If cold weather is expected at night, then watering should be carried out in the morning.
How to properly feed cucumbers?
At the beginning of the growing season, the cucumber needs more nitrogen, during the period of growth in a loop - potassium, during fruiting and the appearance of new growths, nitrogen is again required. Therefore, improper feeding can be another reason why cucumbers turn yellow in a greenhouse.
The main thing to remember is that plants need little, but proper feeding. Cucumbers have weak roots that are not able to penetrate deeper than 20 cm, so plants are especially sensitive to soil properties. Fertilize it with manure, decayed garbage, straw, peat or sawdust.
Enrich the compost with nitrogen and fertilize locally. Do not forget about mineral fertilizers. Over the summer, you need to properly feed cucumbers no more than 5 times. The first feeding is carried out at the beginning of flowering.
The next four are during the fruiting period. They use chicken manure and mullein, but they can also be replaced with ready-made top dressings. When warming comes to replace a long cold snap, greenhouse cucumbers need ammonium nitrate.
Cucumbers are fed by placing fertilizer in the furrows, after which they are watered. During low temperatures, the plant is supported by foliar top dressing.
Cucumbers love warmth.
When choosing a place for planting cucumbers, you need to be guided by such a factor as the absence of a draft. Since drafts and sudden changes in temperature can cause the leaves of cucumbers to turn yellow. You can open the greenhouse only when the temperature inside exceeds 30 ° C.
Moreover, you need to open the doors on each side in turn. Opening from both sides at once, you will allow the appearance of a draft.
How to get rid of pests on cucumbers?
There are a lot of insect pests, as a result of which cucumbers turn yellow in the greenhouse. This is a sprout fly, and a cucumber mosquito, and aphids, and a spider mite.
All these insects or their larvae feed on the leaves, stems and fruits of cucumbers, which inevitably leads to drying and death of the plant. In order to get rid of them and save the plant and crop, it is necessary to choose the right pest control agent. But do not forget - after treating the plant with one or another drug, all grown fruits must be removed and discarded. It is extremely unsafe to eat cucumbers that have been contaminated with drops of pest control agents.
Why cucumber leaves turn yellow is often not so easy to understand, because there are many reasons and it seems that they all fit your case. But you have to do something, because you don’t want to lose the harvest.
How to prevent yellowing of cucumber tops and what to do if cucumber leaves have already begun to turn yellow? Now let's find out.
Why cucumber leaves turn yellow: 6 reasons
The first reason is banal - some of the lower leaves inside the beds turn yellow and die from lack of light. This is not a cause for concern at all, it is normal.
As a rule, a cucumber bed is a real lush jungle, it is not surprising that light penetrates inside with difficulty and the lower old leaves lack it. In this case, just pick off the yellow leaves from time to time and enjoy the harvest. The second reason is a lack or excess of moisture.
In a normal summer, cucumbers are recommended to be watered abundantly two to three times a week, and in hot summer - every day, deeply wetting the ground. Otherwise, the roots of cucumbers will "get out" to the surface of the earth in search of moisture and may dry out.
For plants, this is a disaster, both leaves and ovaries begin to turn yellow. Cucumbers also do not like rainy weather: the roots rot, rot forms on the stems, as a result, we again see yellow leaves. The third reason is fungal diseases.
Most often, it is fusarium, pitiosis and other fungal diseases that cause yellow leaves on cucumbers. First, rusty spots appear on the tops, then the leaves become covered with spots completely, dry out, fall off.
At the same time, in the case of Fusarium, the lashes become sluggish, like a rag, and do not respond to watering. If the thirty-degree heat has been replaced by cold rains and lower night temperatures, hold on: fungi will not keep you waiting. The fourth reason is pests.
The whitefly or spider mite sucks out all the juices from cucumber leaves, as a result, the leaves turn yellow and die. In this case, the recommendations are obvious: a good pest is a dead pest.
You will either have to spray the bed with "poison", or save yourself with folk remedies. The fifth reason is the lack of nutrients. The most unlikely, but still occurring, cause of yellowing cucumber leaves.
If the cucumber leaves turn yellow and the edges dry, they may not have enough potassium or magnesium. Dark green veins against a background of yellowness can signal an iron or manganese deficiency. Yellowing upper leaves occur with a lack of copper.
Feeding will help to correct this situation. Well, the last reason for yellow leaves is old age. Over time, the cucumber leaf coarsens, ages, stops photosynthesis, turns yellow and dies. Most likely, by this time you have already eaten cucumbers to satiety, and the aging lashes do not bother you.
But if you want a fresh cucumber right from the garden until autumn, there are ways to “prolong the life” of cucumber lashes, and we will talk about them later.
What to do if cucumber leaves turn yellow
The best cure for anything is prevention, and cucumber leaf yellowing is no exception. It is easier to prevent this from happening in your garden than to treat it later. Therefore: 1. Try to keep crop rotation.
Do not plant cucumbers in the same place year after year, do not plant them after zucchini or pumpkin, otherwise the likelihood of “catching” a fungal disease increases significantly.2. Water your cucumbers regularly and generously.
If you visit the site only on weekends, do not be too lazy to mulch the beds well with weeds or mowed grass. A thick layer of mulch will not allow moisture to evaporate, as well as provide cucumber roots with additional nutrition and warmth.
After germination in the phase of 3-4 leaves (and then every 10 days), spray the cucumbers with the following composition: 20 grams of laundry soap, 1 liter of milk and 30 drops of iodine per 10 liters of water.5. Another option for preventive spraying: in the evening, soak a loaf of bread in a bucket of water, knead the bread in the morning and add a small vial of iodine.
Dilute one liter of this mixture in a bucket of water and process the cucumbers. If repeat this procedure once every two weeks, you can keep cucumbers green until autumn.6. In June, spill the cucumbers with a solution of soda (1 tablespoon per 10 liters of water).
Then the onion peel is squeezed, the broth is filtered and diluted in a ratio of 2:8 with water. Spray the leaves with this solution from above and below, and then spill the ground.8.
If you still didn’t save yourself and the leaves began to turn yellow, try spraying the cucumbers with a solution of whey or kefir (2 liters per 10 liters of water). For better fruit setting, you can add 150 grams of sugar to the solution.9.
When the leaves are just starting to turn yellow, watering with a weak solution of potassium permanganate can help. 10. To prolong fruiting and rejuvenate aging leaves of cucumbers, foliar top dressing with urea is carried out, while adding humus under the roots.
Spraying with infusion of rotten hay does an excellent job with the same task. To obtain an infusion, hay is soaked in water (1: 1) for two days. Spray cucumbers three times with an interval of a week. eleven.
To protect against pathogenic fungi and bacteria, use biological preparations (for example, trichodermin). They suppress harmful microorganisms, but are safe for humans and animals. We wish you success and great harvests!
How disappointing it is when cucumbers turn yellow in a greenhouse. What is the cause of this trouble and what can be done to save the day and still get a good harvest? If the yellowing of the leaves is not accompanied by wilting, the reason is most likely a lack of nutrients. Why do the fruits and leaves of cucumbers turn yellow? Experts identify several of the most common causes.
Non-compliance with the technology of growing cucumbers in greenhouses
Cucumber is a very moisture-loving plant (like pepper), so you should not neglect the rules for watering this vegetable. These rules are simple: so that the cucumbers do not start to hurt and turn yellow, the water for irrigation should not be cold (watering from a hose is not good). Water should be defended.
During the fruiting period, watering should be increased. In cool weather, plants are watered in daytime, and on sunny warm days - in the morning. If the days are hot, then in the morning watering is done only refreshing, and in the evenings - normal.
The depth of the moistened earth should be sufficient so that the root system of cucumber plants develops in depth, and not superficially. The regularity of watering is crucial: it is only a few times to go astray and skip watering the plants, and this will immediately affect the quality of future fruits. So, the lack of moisture entails the yellowing of the plant itself and the new ovary of cucumbers. Yellow spots indicate a lack of potassium, and light green ones are a sign of magnesium deficiency.
This means that cucumbers need to be fed. Weather conditions often become the reason why cucumbers turn yellow. Cold and wet weather caused by late frosts can damage plants.
If rotting of the ovaries appears, it is urgent to remove the already faded flowers and treat the cut with potassium permanganate (solution). To prevent further bacteriosis, spraying is carried out with either 1% Bordeaux mixture or 0.4% copper oxychloride.
It is worth noting that peppers can also turn yellow and lose leaves if they are in temperature conditions up to +120 ° C for a long time. The composition of the soil is crucial. The lack of nitrogen and the scarcity of the soil is a common reason why the development of the plant is disturbed.
It is important to ensure that there is no overdose in the amount of fertilizer, which, in turn, leads to oppression and yellowing of seedlings and their fruits. Before planting cucumber seedlings and after the harvest is harvested, mandatory manure is introduced into the soil. And during the growing season, fertilizing with complex mineral fertilizers containing phosphorus, fluorine and potassium, and liquid mullein is considered mandatory.
Damage to plants by various diseases or pests
Powdery mildew. If light spots resembling white plaque were found on the leaves, gradually increasing in size, then this is a sign of infection. The leaf dries and turns yellow.
How to deal with this trouble? If you do not worry about measures to destroy powdery mildew, next season it will certainly make itself felt.
The fungicide preparations Topsin, Bayleton, Karatan will help. The main cucumber disease in our area, in which the leaves turn yellow, is downy mildew (peronosporosis). You should also pay attention to varieties of cucumbers that are resistant to this disease. Fusarium wilt. A dangerous fungal disease that causes the death of cucumbers in a greenhouse.
Penetrating into the capillaries of the plant, the spores of this fungus completely block the access of nutrition to the fruits and leaves. In greenhouses where infection has occurred, a complete replacement of the soil is required. In addition, you need to regularly change the variety of plants. Aphid gourds.
Special preparations cope well with these pests: Belofos, Arrivo and the like. Root rot. The leaves, both in young plants and in adults, begin to turn yellow from below. This is caused by significant temperature differences between day and night.
The reason may be watering too "cold" water. Weakened plants fall ill first, then infection through the soil begins to be transmitted to other cucumbers.
Preventive treatment (twice) with Previkur in the root area can prevent this unpleasant disease. Downy mildew (pernosporosis). This disease, common in melons and cucumbers, appears in greenhouses in conditions of high humidity of air and soil, against the background of dense planting of seedlings.
Affected fruits shrink and turn yellow. The first signs of damage may appear immediately with the onset of the fruiting period. In this case, the crop can be completely destroyed.
How to determine that the plants are sick? Sharp-angled, dark green spots appear on the lower leaves. Preparations for combating pernosporosis - Bordeaux mixture or copper chloride oxide (for the first treatment), "Bravo", "Avixil" (for the second treatment after 7 days).