Why do cucumbers have light green leaves. We understand why the leaves of cucumbers turned pale. Dealing with a Problem to Save the Harvest

Why do the leaves turn pale

Gardeners often encounter pathological processes that are manifested by the pale color of the leaves of cucumbers. They depend on which element the plant lacks or, conversely, which nutrients come in excess.

Green leaves turn pale green due to improper care or adverse weather conditions.

Wrong care

Pathological processes do not necessarily indicate a lack of nutrients in the soil. Sometimes it happens that these substances are not absorbed due to improper care. Nitrogen deficiency can manifest itself due to lack of moisture. Too dry soil causes the activity of beneficial microorganisms to fade, available nitrogen disappears, which leads to blanching of the leaves. Seedlings and cucumbers require regular watering.

Some gardeners, without fully finding out the reasons, rush to feed. But an excess of nitrogen will lead to the accumulation of nitrates in the fruits, from which their quality will noticeably decrease. You can eliminate the cause by correct and regular watering - in a week the leaves will acquire a natural color.

If the situation is critical, cucumbers are fertilized, but fertilizing should not be carried out before harvesting.

The appearance on the crop of leaves resembling a dome shape with a light border around the edges often misleads vegetable growers, since the same symptoms may indicate damage to the roots. The detection of yellow, dry roots indicates a serious illness and feeding is indispensable. The root system may turn yellow from an overabundance of certain nutrients in the soil.

Weather

It happens that root system completely healthy, and the plant is fully provided with potassium. But the leaves of cucumbers for some reason lose their former brightness.

This happens due to the long absence of good weather, when the process of photosynthesis is disrupted and trace elements flow from the foliage. With the onset of sunny days, the organs acquire a natural color, and the problem is eliminated by itself.

Lack or excess of micronutrients

Experts identify several reasons why the leaves of cucumbers become discolored. Here are the main ones:

1. A lack of nitrogen is easy to identify by slow growth, thin and hard branches that quickly become woody. The leaves are smaller than usual and point upwards with sharp ends. Lateral shoots are almost not formed, the ovary falls off, most of the flowers dry up. At the initial stage of the disease state, leaf plates turn yellow in old organs, then young organs are affected. Nitrogen starvation eventually manifests itself in the light color of medium leaves and the pale color of cucumbers. At first, thin veins remain green, but they also lose color over time, and even new organs immediately grow light green. pale-colored cucumbers are small in size and become pointed at the end.
2. Excess boron appears pale in green cucumber leaves. Then the green plates acquire a lemon yellow color. With the aggravation of the disease state, light yellow spots appear, surprisingly evenly spaced along the edges of the plates. The rest of the plate, especially the middle part, remains a normal saturated green color. The tissues affected by spots die off and curl up, and the symptoms spread to all organs. Necrotic tissues twist, the disease progresses, which can cause necrosis of the entire plant.
3. With a lack of iron, young leaves lose their color, only the main veins remain green. With the spread of the disease state, the entire plate is affected by chlorosis, all organs are involved in the pathological process. At the advanced stage, their edges die off, but the fruits do not suffer in any way.
4. Excess potassium is manifested by pallor and yellowness of the oldest organs.
5. Calcium deficiency is manifested by the formation of small leaves of saturated green color and short internodes. Young organs become pale green, covered with light stripes. Over time, they become wider, and their affected part dies off.
6. Phosphorus deficiency is very rare. If vegetable growers follow the recommendations and apply all fertilizers, then the plant will be provided with nutrients in full. But this chemical element is poorly absorbed in alkaline soil. The reaction of the soil must be checked with litmus paper. If the fears are confirmed, then the earth is acidified with peat or sawdust. Phosphorus deficiency is manifested by inhibition of crop growth, foliage of small size, dense and watery. After a while they disappear.
7. With a lack of copper, the tips of the plates turn pale and brighten, lose their elasticity and dry out.
8. Lack of molybdenum - leaves lose their rich color.
9. Potassium deficiency provokes yellowing of the plates, and over time they turn brown.

There are cases when an excess of some fertilizers leads to a shortage of others. Most often this happens with nitrogen and potassium. Excess nitrogen is manifested by large organs, numerous flowers, but the ovary is formed later and the fruits ripen longer. An increased concentration of potassium in the soil causes rapid flowering and fruit formation, but crops inhibit growth, and as a result, the yield decreases sharply. At a high concentration of calcium, cultures poorly absorb manganese, zinc and copper.

External symptoms of nutritional deficiencies may be different, but there are also common pathologies in growth and development. An experienced gardener visually determines that something is wrong with the plant.

Solution

The lack of any nutrients negatively affects the growing season of cucumbers, as well as their yield. It is urgent to carry out top dressing with the necessary fertilizers. The concentration of the solution should be low, up to 0.3%.

In most cases, nutrient deficiencies are observed on infertile soils, but it is also impossible to make highly concentrated top dressings, as this will cause plant poisoning. You can carry out foliar top dressing with a 0.1% solution of the necessary fertilizer.

With prolonged cold and cloudy weather, complex top dressing is carried out in a foliar way: they take 5 g of potassium chloride, ammonium nitrate and superphosphate per bucket of water. The solution must stand for 24 hours. Foliar feeding of cucumbers is recommended in June. Fertilizers are applied in the evening so that the seedlings do not suffer from the scorching sun.

Disease prevention

Prevention pale leaves in cucumbers it helps to prevent the development of a painful condition. It includes the following activities:

1. Fertilizing plants every 14 days. It is not recommended to fertilize in dry soil or early in the morning. It is best to water the plants in the morning and fertilize in the evening. Do not exceed the dose of fertilizer indicated on the packaging by the manufacturer.
2. Compliance with crop rotation.
3. timely and regular watering cultures.
4. Mulching the soil as protection against premature evaporation of moisture.
5. Constant monitoring of air humidity in greenhouses.

For feeding use as mineral fertilizers, as well as organic. Treatment of plants with a solution consisting of laundry soap (20g), 30 drops of iodine and a liter of milk two weeks after germination helps to strengthen their immune system and even protect them from certain pests.

VISLOPLODNIK (ECCREMOCARPUS) fam. bignoniaceae

Conclusion

According to external symptoms, experienced vegetable growers identify a deficiency of one or another chemical element and eliminate the painful condition with top dressing. But it is best not to wait for these alarming signals, but to fertilize according to the instructions of specialists, depending on the composition of the soil. Then the painful condition can be avoided, and as a result, a good harvest can be obtained.

We will analyze with you the signs of a shortage of one or another element for cucumbers and, on the basis of this, we will see in what cases and how to feed the cucumbers at the stages of their growth and development.
Often, vegetable growers observe a change in the color of the leaves of cucumbers. And indeed, she says a lot: a border along the edge of the sheet and dark green veins - a lack of potassium; pale yellow color next to the corolla of the flower - little phosphorus. Insufficient development of apical buds and the appearance of leaves in the shape of a dome - cucumbers do not have enough calcium.

A change in the color of the leaves, the appearance of certain signs of a lack of nutrients in plants does not mean that they are not enough in the soil. The assimilation of nutrients often depends on external conditions. For example, if you observe signs of a lack of nitrogen (leaves turn pale), then first of all you need to check whether watering is done regularly. Overdrying of the soil leads to a partial attenuation of the activity of beneficial microorganisms, the disappearance of available nitrogen, and therefore the leaves turn pale.

However, do not rush to feed the plants. Fertilizing with fertilizers containing nitrogen, especially during the period of fruit formation, increases the content of nitrates in them, the quality of fruits is noticeably reduced. Sometimes it is enough to start watering cucumbers correctly and regularly, and within a week the color of the leaves is restored. Well, if things are really bad for plants, then cucumbers can be fed with ammonium sulfate or urea at the rate of 10-15 grams per 10 liters of water. Cucumbers should not be fed before picking or on the eve of picking fruits.

The appearance of dome-shaped leaves with a border around the edge often misleads gardeners, since exactly the same signs of the disease occur in plants with damage to the root system. Therefore, before feeding cucumbers with calcium or potassium, it is worth checking how the roots look. If you see that the roots have turned yellow, then feeding such cucumbers is unlikely to help. Most likely, it will aggravate the situation even more, especially if the cause of the root disease was increased concentration elements in the soil solution, which occurs when mineral fertilizers are applied in excess.

But it may be so: the roots have a normal, white color, but the symptoms of potassium deficiency are not confirmed. This happens when, due to long cloudy and cold (below 15 degrees) weather, there is an outflow of nutrients from the leaves. The color of the leaves usually recovers with the onset of warm days.

If, nevertheless, cloudy weather lingers, it is useful to spend foliar top dressing complex fertilizers: you need to take 5 g of potassium chloride, 5 g of ammonium nitrate and 5 g of superphosphate, previously infused in water for a day, for 10 liters of water.

Cucumbers respond especially well to foliar feeding in the first half of the growing season. Such top dressing is carried out at the end of the day so that the moistened leaves are not damaged by the action of the sun's rays.

Now a little about phosphorus starvation. Its symptoms are very rare. If superphosphate is introduced into the soil according to the recommendations, then cucumbers will be fully provided with them. But still, we must remember that phosphorus is poorly absorbed when the soil is alkaline. Soil reaction is easy to check with litmus paper. In this case, the soil substrate should be acidified - add sawdust or sour peat.

chapter 1. Why do cucumber leaves turn pale

Lack of nitrogen. Signs of nitrogen deficiency are clearly visible in the spindle-shaped habit of plants. Growth is strongly inhibited, the lashes are thin, hard, quickly woody. The leaves remain small and most of them are directed upwards. Very few side shoots are formed. The ovaries are strenuously showered and some of the flowers die. First, premature yellowing of the leaf blade is observed on older leaves. It quickly spreads to young leaves. With a later onset of nitrogen starvation, yellowing can also capture middle-aged leaves. With progressive nitrogen deficiency, the fruits acquire a pale yellow color. At first, the thinnest leaf veins still retain green color, but subsequently they also lose their green color and even new leaves acquire a lighter color. Individual fruits lose their normal color, they are shortened in size and have a pointed end.

Boron excess. The first sign of excess boron intake in plants is the lemon-yellow color of the edges of old leaves. Later, small light yellow, rather evenly distributed spots appear along the edges of the leaves between the veins. The rest of the leaf, especially its middle, retains its normal green color. These spots then become necrotic, and signs of excess appear on young leaves. The edges of the affected leaves after a while are bent down. The death of tissues until complete necrosis of the leaf occurs between the veins, but does not have clear boundaries.
Iron deficiency. Signs of chlorosis appear on the youngest leaves of the main and side shoots. Only the main and lateral veins retain the green color. The entire plate acquires a light green color. Over time, the edges of the leaves become necrotic, and chlorosis spreads to older leaves. There are no signs of iron deficiency on the fruits.
Excess potassium. Visual signs of an excess of the specified element appear along the edges of older leaves.
Calcium. A lack of calcium in a cucumber causes the appearance of small leaves of a dark green color, the internodes are short. Then, young leaves lighten from the edges, and at the same time, narrow light stripes appear on the leaf blade between the veins. They expand, lose their green color, necrosis. The veins and the adjacent part of the leaf retains an intense green color. The edges of the sheet are folded down.
Copper. The lack of copper causes whitening of the tips of the leaves of the plant, lose turgor, fade.
Molybdenum. With a lack of molybdenum, a weakening of the green color of the leaves is observed. The lack of this element accompanies the violation of nitrogen metabolism.
When a plant lacks potassium, it first turns yellow, and then the edges of the leaves turn brown. If the soil is peaty, then the leaves begin to wrinkle. With nitrogen starvation, the leaves are stunted, turn pale, especially the lower ones, the fruits are shortened and pointed (you probably got such cucumbers!).

The lack of phosphorus is accompanied by a sharp slowdown in the growth of your green wards, the leaves become smaller, become dense, watery spots appear on them, and after a while the damaged leaves die off.

chapter 2. How to deal with such a problem

Everyone knows that the lack of nutrients adversely affects the growth and development of plants, which naturally affects the quantity and quality of the harvested crop. Today I will talk about how our most common favorite vegetables react to the lack of basic nutrients - nitrogen, phosphorus, potassium. And also about what to do if you, by external signs, have determined the lack of one or another element.
What to do if there is a lack of elements in the plant?
It is necessary to prepare a nutrient solution of low concentration from 0.2 to 0.3%, that is, for 10 liters, take from 20 to 30 g of the necessary fertilizer. More often, a lack of elements is observed on soils poor in humus, but on such soils it is dangerous to apply large doses of mineral fertilizers, since this can lead to poisoning of the plant. Spraying the leaves (foliar feeding) with a weak fertilizer solution (10 g per 10 l) gives a good effect.
Can an excess of one fertilizer cause a deficiency of others?
Most often, plants react to an imbalance of nitrogen and potassium. With an excess of nitrogen, plants "fatten", that is, they form large leaves, powerful stem, observed abundant flowering, but the setting of flowers occurs later, the fruits ripen more slowly. The increased content of potassium in the soil leads to an acceleration of flowering and fruiting, and the plants are small, the total yield is reduced. High content calcium in the soil leads to a decrease in the absorption of manganese, copper and zinc.
What kind vegetable crops most sensitive to chlorine?
These crops include cucumber, pepper, tomato, potato. Under these crops, it is undesirable to make potassium salt and potassium chloride. They should be replaced with potassium nitrate or potassium sulfate. Compound fertilizers that do not contain chlorine can be used.
How do fertilizers affect the quality of vegetables?
Leaf vegetables with a lack of nitrogen sharply reduce the yield, the leaves become hard, coarse, and an excess of nitrogen fertilizers with a lack of phosphorus and potassium, as well as poor lighting, leads to the accumulation of nitrates, cabbage heads are poorly stored. With excessive nitrogen nutrition, the keeping quality of root crops is sharply reduced.
Increased doses of phosphate fertilizers improve the quality of fresh and pickled cucumbers and tomatoes. In a tomato, with a sufficient amount of potassium in the soil, taste qualities increase.
What should be done when the first signs of phosphorus deficiency are detected?

It is necessary to add superphosphate to the soil (per 1 square meter- 1 tablespoon), or phosphorous flour (per 1 square meter - 2 tablespoons), or any other fertilizer containing phosphorus. It should also be noted here that early liming of soils with an acidic reaction improves the phosphorus nutrition of plants.
It is possible to feed the cucumbers with potash fertilizers before fruiting (20 g per 10 liters of Takuya). water top dressing repeat 3-4 times a month, if required by the condition of the plants. A good mineral-organic top dressing with micronutrient fertilizers is also a solution (in 10 liters of mullein) 1 kg of water, 30 g phosphate fertilizer, 20 g of potassium, 2 g of copper permanganate and 1 g of potassium vitriol and boric acid.

If the cucumber lashes are thin, the leaf is small and pale, then feed with nitrogen. With a strong growth of lashes and fruiting delay, give top dressing with phosphorus and potassium. If there are few ovaries, it is necessary after
top dressing with bird droppings (mullein droppings) to reduce the temperature in the greenhouse to 18 ventilate (degrees at night). If there are a lot of ovaries, they require enhanced feeding with mullein (if), then a change in the feeding scheme with litter - the transition from alternating organic and mineral fertilizers to two 2: 1 (organic fertilizer once, mineral fertilizer once).

Both mineral and liquid fertilizers organic, apply under the root, without polluting the leaves.

Do not forget about foliar top dressing, especially those in which the development of dangerous diseases is prevented - false powdery mildew etc. Such top dressing can serve as a solution (per 10 liters of water) 20-30 g of urea and 2 g blue vitriol, boric acid and potassium permanganate.

chapter 3. Prevention of pale leaves

It is necessary to help the plants and make top dressing. But how do you know what?

Why the recommended doses of fertilizers are not always effective. The reason for this is that our soils are very different in their chemical composition, and the content of vital nutrients in them is not the same. All nutrients are divided into macro- and microelements. Macrofertilizers are applied in large quantities. These are nitrogen, phosphorus and potash fertilizers. Doses of microfertilizers are small, but their role in plant life is also great. They are part of vitamins, enzymes - living catalysts for reactions in organisms, both plants and animals.

External signs of a lack of fertilizers in different plants are different, but there are general changes in growth and development caused by a lack or excess of nutrients. Visual diagnostics is a simple and accessible method for every amateur vegetable grower to determine the needs of plants for fertilizers. I want to draw their attention to the external signs of a lack or excess of certain chemical elements in various cultures.

With a lack of nitrogen, inhibited growth, short and thin shoots, small inflorescences, weak foliage plants, weak branching, small leaves of pale green color. Moreover, the yellowing of the leaves begins with the veins and the part of the leaf blade adjacent to them, and the parts of the leaf remote from the veins can still retain a light green color. The veins of the leaf with a lack of nitrogen are also light. Yellowing begins with the lower, older leaves.
By external signs, one can judge the lack of one or another nutrient in the soil and the needs of plants for top dressing, which should be carried out without delay as soon as the plants show the first signs of deficiency, and it is better not to allow these SOS signals to appear at all. However, growth slowdown and change appearance plants are not always due to a lack of these nutrients in the soil. Similar signs are sometimes caused by damage to plants by pests or diseases, as well as unfavorable growing conditions (drought, low temperature etc.). It is important to be able to distinguish between these changes and signs of nutritional deficiencies.

Today, trade organizations offer amateur gardeners a lot various fertilizers. Do not rush to buy the first one that comes across. It is good to use complex fertilizers, especially with the addition of trace elements. For each crop, a certain composition of fertilizers is produced in different phases of development. And what is suitable for potatoes in the second half of summer is not suitable for feeding young cucumber plants in greenhouses. In addition, different soils also cause for the same crop different composition top dressing.

Usually do wet top dressing. The required amount of fertilizer is diluted in a bucket (or liter) of water and the plants are watered with this solution over an area of ​​1 m, and then a bucket is poured onto the plants clean water so that there are no burns. If your plants are very lagging behind in development, it makes sense to do foliar feeding. The concentration of the solution should not exceed 1% in this case. Nutrients through the stomata will be absorbed by the leaves and immediately used by them. Dry top dressing before rain or watering should be done carefully. To do this, you can adapt a dense plastic bag small size. Carefully cut off a small corner of the package with scissors. Pour fertilizer into the bag, after thoroughly mixing and crushing all the lumps. We carry this bag between rows of cucumbers, carrots, parsley, onions and other crops, almost touching the ground with them. Fertilizers through the cut hole will evenly spill out onto the soil surface and there will be no danger of them getting on the plants even if the rows are close.
In order for cucumber seedlings to develop normally, they need to be fed. The first feeding is recommended 8-10 days after germination. If you prefer to feed cucumbers with organic fertilizers, then it is advisable to add 20 g of superphosphate to 8-10 liters of mullein solution to a mullein solution (1:10).

To feed seedlings of cucumbers, you can also use complex fertilizers, which include not only nitrogen, phosphorus, potassium, but also other micro and macro elements necessary for plant nutrition.

In the future, top dressing seedlings of cucumbers are carried out once every 2 weeks. Top dressing can not be carried out on dry soil or in the morning. It is recommended to water the plants in the morning and fertilize in the evening. If you are using mineral fertilizers for the first time, do not exceed the dosage recommended by the manufacturer. The recommended dose of fertilizer can even be halved, otherwise it is easy to burn tender plants.
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. 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 prevent moisture from evaporating, and will also provide extra nutrition and warmth to the cucumber roots.

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. 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.

Lack of nutrients causes a change in color, shape of cucumber leaves. But in order to figure out what is missing, or what has been contributed in excess (this also happens), you need to decide how the leaves turn yellow:

• the entire sheet plate;

• along the edges;

• in the form of spots;

• the leaf loses its greenness between the veins, although they remain green.

As you can see, there are many options. You need to inspect the cucumbers and try to identify the problem yourself. Otherwise, the crop may disappear, because with some symptoms, the ovaries are shed. And losses begin with a banal yellowing.

The second question, if the cucumbers are pale green - how to feed.

Possible reasons for the loss of green color in cucumbers

Nitrogen is responsible for the accumulation of green pigment in plant leaves. But if the root system is weak, then it will not be able to absorb nutrients, even if they are in the soil. Therefore, the cause must be looked for deeper.

Roots may be underdeveloped due to alkaline soil reaction. If lime was added to it, then phosphorus nutrition will not be available to plants, since phosphorus itself has a high pH.

For full decomposition, it needs acidic neighbors - nitrogen and potassium. With phosphorus starvation, the foliage turns yellow unevenly - yellow-brown spots appear, which dry out after a couple of days.

It turns out a chain reaction: plants do not absorb phosphorus, because it is not available to the roots. Due to the lack of phosphorus, nitrogen is not absorbed. You need to look first of all at the roots of cucumbers.

If they turn yellow, then fertilizing with mineral mixtures will not help - most likely - the plants will die. If the root system white color, then you can start with spraying with urea. This fertilizer is best absorbed through the leaves, so the effect will be fast.

If a lower leaves cucumbers are light green, than to feed - only with nitrogen. Because the lack of nitrogenous substances begins to appear first on the old foliage, and then passes to the young tops - they also begin to turn yellow, dry and die.

Important! With nitrogen starvation, there are other signs that you need to pay attention to - thin shoots of cucumbers, small leaves, fruits with pointed tips, few flowers and ovaries

Another important element nutrition of cucumbers during the fruiting period - potassium. With a small amount in the soil at the beginning of the fruitful period, the foliage may begin to turn yellow around the edges. Potassium starvation can be distinguished from nitrogen starvation only by the marginal “burn” of foliage. With nitrogen, the leaf suffers completely.

The yellow edge of the leaf subsequently dries up and dies.

Potassium starvation can also occur with a lack of phosphorus. Due to such a close relationship, these elements contribute simultaneously. Potassium is absorbed faster by cucumbers, as it is needed for the formation of fruits and their ripening - it can be added during the growth of cucumbers. Phosphorus is consumed more slowly, dosages are usually enough for the entire fruiting period.

Lack of trace elements - light leaves in cucumbers

The brightening of the foliage of cucumbers causes, first of all, a lack of copper. Appears at the tips of the leaves. The process begins with medium leaves - 4 - 5 below the top. Additional signs of copper deficiency:

• ovaries and flowers fall off;

• the plant becomes smaller, turns into a dwarf.

Manganese, or rather, its lack, also contributes to the appearance of chlorotic spots. The process is noticeable between the veins of the cucumber leaf plate. The veins remain green. The problem starts with the middle leaves.

With zinc deficiency, yellowing extends to the veins of cucumber leaves. The plant becomes mottled - shades of yellow, green and bronze are present.

Iron deficiency in the soil causes uniform yellowing of young leaves. The process will soon spread to the old foliage, if no action is taken and top dressing is not applied.

Calcium is one of the most important trace elements that are fed to plants for fruit ripening. Chlorosis with a lack of calcium begins between the veins and along the edges. The veins themselves and the area adjacent to them remain green.

Magnesium is involved in the formation of chlorophyll - the green substance of cucumber leaves. A deficiency can weaken the plant and cause it to develop blossom end rot. Old leaves are the first to suffer - they lose color and become deformed.

If cucumbers have pale leaves, you need to decide what to feed. More often and easier to buy a solution of trace elements and spray with an interval of a day or two until the balance is restored.

soil care

With insufficient watering, the formation of chlorophyll stops, because the activity of beneficial microorganisms stops. And plants can absorb nitrogen only after it has been taken up by bacteria.

In this form, nitrogen fertilizers are available to cucumbers. What to feed - the second question. First you need to make sure that cucumbers get enough water, because they love moisture in both the soil and in the air, because they come from rainforests.

As soon as it normalizes water balance, cucumbers can independently restore the color of the leaves. Especially if top dressing was made regularly and there should not be a shortage.

If the soil is cold - this happens when the temperature stays below 15 degrees for several days in a row, then nutrient balance is disturbed. The reason is that the activity of soil bacteria stops and the plants do not receive the nitrogen they need.

The leaves of cucumbers turn pale, but this phenomenon is temporary, therefore, with the onset of warm weather, everything is restored. To help plants in such a situation, you can use complex fertilizers and carry out foliar spraying.

Fertilizers can be both purchased and mixed independently. It is imperative that they be three-component, if the situation has developed in the first half of the growing season - in the spring, when temperature drops still occur.

If cucumbers have pale leaves - how to feed

To balance the nutrients in the soil, you can use both organic and mineral fertilizers for cucumbers. There are a huge number of species of both. You don't need to use everything at once.

Video: Feeding cucumber in the 4-5 leaf phase

Knowing the type of soil on the site and the needs of cucumbers, you can choose 2 - 3 types of mixtures and a solution of microelements to maintain the right amount of nutritional components.

Carefully! Plants can be poisoned by mineral nutrient mixtures if they have never been used outdoors. In this case, it is necessary to start applying top dressing not according to the recommendations in the instructions, but in doses two times smaller than those indicated.

Nitrogen-potassium fertilizers

The most nutritious and safe are organic top dressing for cucumbers, if the leaves are pale or have begun to gradually lose color. It is recommended to use overwintered manure or mature compost.

The problem is that not all gardeners constantly live in the country, but they go there occasionally and cannot devote much time to growing plants. In this case, you can order manure from vendors or buy granulated chicken fertilizer in a store to feed cucumbers a couple of times.

Manure, chicken manure contain a large amount of ammonia, potassium and trace elements. Soil bacteria are very fond of such top dressing and process them quickly.

How to use fresh manure so as not to damage the roots of cucumbers.

• First, it must be insisted so that the excess ammonia disappears. To do this, a third of the bucket is filled with fresh manure and poured with water for a week. Stir the mixture periodically

• When infused dilute each liter with 10 liters of water

Irrigate at the root about 1 liter for each cucumber bush.

Chicken manure is a very concentrated fertilizer containing a large amount of ammonia that can burn the root system in a matter of hours. Therefore, it is insisted in the same way as the mullein, but dilute a liter of solution in 20 liters of water.

Wood ash is a valuable organic fertilizer that can improve matters with a lack of potassium and phosphorus, if the cause of yellowing of the leaves is the underdevelopment of the roots. Contains potassium, phosphorus and trace elements about 30 titles. This is enough to restore the balance in the nutrition of cucumbers.

To prepare a solution wood ash for irrigation, you need take 300 g of the substance and pour a bucket of water for 3-4 days. Then you can water under the root. To prevent chlorosis, ash is applied to the soil in autumn. Wood ash is a valuable food for microorganisms. Enough dig up the ashes with soil once every 2-3 years.

Do not mix ash solution with nitrogen fertilizers- they neutralize each other and become useless for cucumbers. With simultaneous application, you need to add ash under the root, and spray the leaves with urea.

Mineral mixtures

The simplest and fastest fertilizer is urea. This is a concentrated substance containing up to 46% nitrogen. It is sprayed with fungus-sick plants, with nitrogen starvation. It is necessary to dilute urea from calculation of 50 - 100 g of the substance per 10 liters of water. Enough solution for 200 square meters.

A feature of urea is the large loss of matter on alkaline or neutral soils. Therefore, if you overdid it with lime, then it is better to make it in a foliar way. Mix with alkaline substances - dolomite flour, ash is also impossible. It is better to apply superphosphate with urea separately: phosphorus to the soil, urea to the leaves.

If the leaves turn pale, you can use two or three-component purchased fertilizers for emergency feeding of cucumbers:

• azophos - two-component, contains nitrogen and phosphorus;

• diammophos - 2 food components;

• nitrophoska is a three-component mixture containing nitrogen, potassium and phosphorus.

A feature of all mineral complex mixtures is the mandatory presence of either all three elements at the same time, or nitrogen and phosphorus. This confirms the version that the root system must develop in the first place, so that the cucumbers have the opportunity to grow, fill and ripen.

Every hostess knows how troublesome it is to grow cucumbers. They sometimes seem whimsical and require a lot of care and attention, or for no reason, they can arise different kind problems, one of which is the pale color of the leaves of cucumbers. Why does this happen, what are the reasons for this phenomenon, what to do and how to deal with this problem correctly and effectively, how to prevent it? We will help you answer these questions.

In fact, there are many factors that affect the color of the foliage. I bring to your attention the main ones. First of all, cucumbers are very susceptible to temperature changes. If the seedlings were transferred to the ground, and then frosts suddenly set in, our vegetable will very often react to this with a faint light green tint of leaves.

Weather conditions affect young plant when the temperature differs greatly between day and night (hot during the day and cool at night). There is one here little trick: it is simply necessary to cover the cucumbers with a film until abundant heat is restored. In this case, you can protect the foliage and the vegetable as a whole.

fertilizers

Many gardeners adhere to the principle: the better to feed the soil, the more good harvest available. There is one here small nuance: in no case should you overdo it with the dosage of fertilizer. Why? The fact is that its excessive amount can cause the appearance of pale leaves. From this it follows: in order to prevent the development of our problem, we need to carefully feed the soil, without much fanaticism, adhering to the norms.

Growing this culture, it is very important to focus on the fact that a large number of ovaries also have a huge Negative influence for cucumbers (more than 20 ovaries on one cucumber). Why is it so? The leaves and weaves then weaken, and our problem arises. It is very simple to deal with this: you need to monitor the number of ovaries and pinch the extra ones.

Watering mode

Cucumbers are very fond of moisture, so they need to be constantly gratified in this so that the leaves and fruits do not weaken. But you can’t overdo it either, otherwise the vegetable will wither. Don't forget to water cold water not worth it at all because it can lead to a detrimental effect on the color of cucumber leaves. It is better to take water at medium room temperature.

The main reasons for the appearance of faded cucumber leaves should also include pests. In this case, we are talking about melon aphid. It is located on back side leaf (it is easy to detect by turning the leaf to the other side) and feeds on our plant. As a result, we get the problem under study. The danger is also manifested in the fact that aphids, having exhausted one area, move on to the next - a large-scale affected area appears.

There are many options for treating plants for aphids. Well-known method- washing the leaves with soapy water or spraying with herbal infusions.

The lack of nitrogen in the soil is another reason for the pale shade of cucumber leaves. Experienced gardeners argue that in this case it is advisable to feed the plants. There are several recipes for how to do this: water each bush under the root with mullein (1 liter of slurry per 10-liter bucket of water); you can also use a weed infusion diluted with water (1 part green to 5 parts water), urea (2 tablespoons per bucket of water) or ammonium nitrate(50 grams per bucket of water).

It is necessary to pay attention to the fact that whitish spots of a rounded shape do not appear on the leaves. The fact is that after some time they grow - thus a whitish coating appears. The leaves themselves become pale in color, become wrinkled and dry out. Why is it so? Similar symptoms are powdery mildew. The plant is affected as a result of constant planting in the same place or due to irrigation with cold water.

Video “Why do cucumber leaves turn yellow?”

This video analyzes the most common causes of yellowing leaves, as well as good advice experienced professionals for effective fight with this problem.

How to fight?

To get rid of such a disease, you can use this effective tool like spraying with a weak solution of potassium permanganate. However, there are many other drugs on the market that are also great for fighting, but do not forget that sometimes it is better to use the old "grandmother's recipes", folk methods than chemistry, which can kill pests, rid the plant of the disease, and at the same time invariably leave its mark on the fruit.

One more no less effective method- this is to give the soil the opportunity to rest, and not to plant cucumbers in the same place for several years in a row.

In the process of caring for cucumber seedlings, gardeners may notice that in some plants the tops lose their rich green color, and the vine itself becomes lethargic over time. Why do cucumber leaves turn pale, and what can this effect be connected with - the quality of soil fertilizers, the frequency of irrigation, or an unsuccessfully chosen seed variety?

The main cause of pale foliage in cucumbers is called a lack or, on the contrary, an excess of certain micro- and macroelements. In most cases, a violation of the balance of nutrients entails a deterioration in the growth and presentation of cucumbers, but after taking appropriate measures, the fruiting of damaged bushes is fully restored.

The blanching of cucumber leaves occurs when there is a shortage of the following elements:

• Nitrogen. The deficiency of this substance is reflected in the development of seedlings and the modification of all elements of the tops - the weak formation of lateral lashes and leaves, the fall of inflorescences without the formation of green ovaries, but the most indicative moment is the spread of yellowness on mature leaves of seedlings. If not submitted on time nitrogen fertilization, the upper leaves begin to turn yellow and in last turn those that are above the first two shoots. It is possible to differentiate the lack of nitrogen in cucumber seedlings according to a peculiar scheme of covering the leaf with pale yellowness - the veins remain green until the last moment and lose color before falling off.
• A decrease in the activity of photosynthesis with a lack of iron is immediately detected in the form of a loss of green color in young plants. Further inactivity results in the appearance of a dry edge along the perimeter of the damaged leaves, and the “washout” of the intense green color passes to mature leaves. The yield of cucumbers does not suffer from iron deficiency.

• Calcium. Already formed leaves almost do not react to a lack of calcium, but young released leaves turn out to be very small and have an unnaturally dark shade of green. After a short time, new leaves begin to lose color around the edges and from the center. Paleness spreads in stripes along the surface of the leaf, without affecting the veins, then these areas die off, and the damaged edges are bent down.
• Light green, and then almost colorless tops of the leaves, with a parallel wilting of the whole plant, indicate a lack of copper.
• The fact that the leaves on the plant first began to turn yellow, and then acquire a brownish tint and shrink, will indicate a potassium deficiency. The presence of a large amount of peat in the soil composition will aggravate the progression of leaf damage with a lack of potassium.

• Phosphorus starvation stops the growth of the cucumber bush - the vine stops reaching up, and the leaves on it become small and hard, as if leathery. Soon, the modified leaves become covered with pale green spots, similar to water stains, and fall off.

With excessive enthusiasm for boron-containing dressings, the gardener risks causing plantings to irreversible changes and the death of the entire crop. The first sign that you should urgently stop using boron will be the acquisition of mature leaves of a rich yellow color around the edges. Soon, the yellowness spreads to the center in the form of spots that begin to dry out and wrinkle the leaf. Feeding the plant with any type of fertilizer should be temporarily stopped.

Why cucumber seedlings lose their green color - other reasons

What to do if the pallor of the leaves of cucumbers is noted during the period of active growth and development of the bush? First of all, determine the cause, and then act in such a way as not to reduce the fruiting of plants:

• Too early planting cucumbers in open ground. If you transfer cucumbers to a permanent place of cultivation, when the warming of the soil has not reached the desired temperatures, the leaves on the seedlings can not only brighten, but also fall off. The only measure to eliminate the problem is to make a mobile tunnel greenhouse on arched racks right above the bed until the earth warms up enough.
• Too much organic matter in the fertilizer. Feeding materials such as chicken manure should be temporarily abandoned. How to feed cucumbers in this case? It is best to use neutral mineral fertilizers - ash or bread solutions.

• Lack of moisture in the soil or cold watering. The reason for the blanching of plants may lie in the irregularity of watering or the freezing of the roots under the influence of cold tap water. You can correct the situation by setting an accurate irrigation schedule and using insulated and settled water for these purposes.
• Excessive number of ovaries on the lashes. Green fruit formations draw vitality from the plant, causing the seedlings to become lethargic and the entire plant to lose color intensity. The number of fruit units should be reduced, distributing them evenly over the lashes, as they decrease towards the top.

Pinching the ovaries is very important point in the formation of a fruit bush. On average, it is believed that one plant should not have more than 23 ovaries at the same time, otherwise it will not cope with the load and will begin to turn pale.

Causes of blanching leaves - seedling diseases

Seedling diseases leading to the loss of color of the green part of the plant are more likely to occur in cucumbers in a greenhouse, since fungal and viral infections spread faster in a stuffy and humid atmosphere. Caring for plants in a greenhouse is also complicated by the fact that it is necessary to monitor the constant flow of fresh air.

There are five most common diseases of cucumber seedlings, due to which the leaves of plants become pale:

• mosaic disease. With this disease, which affects cucumbers both in the greenhouse and in the open field, the leaves of cucumber seedlings are covered with a spotty pattern of yellowish or pale color. Then the leaves of the cucumbers are tucked around the edges and shrivel. The disease spreads when infected seed material is planted or when diseased plants come into contact with healthy ones. The damaged part cannot be repaired. If the disease coverage area is not large enough, the damaged areas are removed, and the entire plant is irrigated with 1% fat milk. Heavily affected cucumber seedlings should be removed and the soil disinfected.

• Powdery mildew is a whitish, lime-like coating that covers the green leaves of cucumbers, mostly outdoors. The disease is activated in wet weather when strong wind, watering or rain, and extends not only to the leaves of the plant, but also to the stem of the vine and even to nearby crops. If the leaves of cucumbers are characteristically pale in greenhouse conditions, then excess moisture or poor soil treatment before planting is to blame. Plants are cured with a composition of mullein and urea, taken in a ratio of 1: 50.

• Peronosporosis. The principle of coating the leaf with plaque in case of peronosporosis resembles the signs of powdery mildew, only the color of the plaque is not white, but yellowish on the upper leaf plate and grayish on the bottom. When the gardener is inactive, the spots characteristically darken, and the sheet is deformed and dries. Causes of the disease: firstly, excessive watering, and secondly, unstable air or irrigation water temperatures. The fight against the fungus includes: limiting soil moisture up to the complete cessation of irrigation, removing damaged leaves and spraying the whole cucumber with an Oxychom solution (two tablets per bucket of water).

• Root rot. The fungus spreads to the plant from the roots, and first covers the lower tier of leaves with pale yellowness, and then moves to the next ones. Following the defeat of the leaves, the entire whip begins to die off, and the plant dies - it rots on the vine. The causes of the disease are called immoderate watering, thick planting, in which the spores of the fungus pass from a diseased cucumber to a healthy one, as well as high humidity and stuffiness in the greenhouse. Pale leaves should be removed immediately, and diseased plants should be sprayed with Infinito 61 SC solution.

• White rot is another reason that the leaves on cucumbers have turned pale. You can find the fungus under the lower lashes of cucumbers, closer to the roots - jelly-like weeping spots appear there, which later become covered with white fluff. White rot quickly spreads along the vine, affecting the stem and most of the leaves. Green ovaries can also become white, especially those hanging on the lower lashes. The fight against rot begins with the removal of damaged areas of the plant that have turned white, and, with a small area of ​​\u200b\u200bthe affected area, sprinkling the cucumber bush with a dry mixture of chalk and lime. Plants completely affected by the disease will have to be removed.

With close landings, characteristic greenhouse cultivation, not only diseased plants, but also all those in the immediate vicinity are examined and treated with solutions.

In the case where the disease is soilborne, i.e. all kinds of fungal infections, Special attention is given to the disinfection of the soil at the site of the removed bush.