Causes of the yellowness of the cucumber leaf - from improper care to disease

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When the leaves of cucumbers turn yellow, inexperienced gardeners begin to panic. An experienced vegetable grower already knows that yellowness is not always so dangerous, but still the culture requires increased attention. A detailed analysis of the reasons will help preserve the health of cucumber plantings in case of yellowing of the foliage. More often the problem is eliminated by ordinary methods, less often it is necessary to treat bushes from pests and fungi.

Cucumber leaves are drying

Why cucumber leaves turn yellow: analysis of all reasons

Most often, the cucumber culture suffers from improper care. The amount of light, moisture, temperature fluctuations affects the state of the foliage. Already at the stage of planting seedlings, plant health is laid in the ground. It is influenced by the degree of thickening, protection of the place from drafts and direct sunlight. Less often, cucumber bushes begin to turn yellow from hunger (lack of nutrients in the soil) and diseases - fungus, bacteria, viruses and pests. Let's take a closer look at the main causes of the problems.

Dried cucumber lash

Improper care

The most common reason is non-compliance with the rules of care, although they are quite simple. With a minimum of knowledge, the grower can avoid the problem of yellow spots on cucumber leaves.

Major mistakes:

  • Too much water. Cucumbers are moisture-loving, but everything should be in moderation. Plants not only turn yellow from transfusion, but also wither and rot. Frequent watering washes nitrogen, potassium and other substances deep into the soil, depriving the plant of nutrition.
  • Yellow spots on the leaves are a consequence of drought. Violation of watering in the other direction also negatively affects the culture - the cucumbers are thirsty and dry up. With dryness, yellowing and drying can often be observed along the edge of the leaf, but sometimes this is also a sign of fungal infection.
  • Dry air, as well as insufficiently moist soil, can cause yellowing and curling of the leaf blades.
  • The bushes are freezing. Hypothermia is a common cause of yellowing of leaves growing outdoors. Low temperatures, coupled with constant exposure to drafts, are detrimental to cucumbers.
  • Not the most obvious reason - the leaves are in contact with the cold greenhouse cover.
  • The leaves are covered with yellow spots from the scorching sun rays. Most often this happens when watering was carried out on a hot day, drops of moisture hit the foliage, and then rapidly evaporated, leaving a burn.
  • Lack of light is observed with thickened plantings and greenhouse cultivation. More often in this case, the lower half of the bush suffers.
  • Mechanical damage to the roots due to inaccurate transplantation does not allow the bush to quickly take root on the site. Rough loosening and untimely removal of weeds can damage and weaken the roots.

Yellowed cucumber leaf

Lack of nutrition

The first signal about a lack of nutrients in cucumbers is not only yellowing, but also curling of the foliage. The main scarce element for foliage is nitrogen. If nitrogen fertilizers were not applied, you can see that the leaf turns yellow, turns pale and curls downward.

Magnesium, potassium, phosphorus - macroelements, along with nitrogen, are necessary for the full development and productivity of cucumbers. The leaves immediately react to a deficiency of these important substances with yellowing, especially those located in the lower half of the bush. Often in this case, the border of the leaf turns yellow.

The plant also lacks trace elements. In this case, the sheet is pulled out. If there is not enough manganese and iron, darkening of the veins can be detected.If copper is in short supply, the upper leaves turn yellow. The problem is solved by complex feeding.

It is important to understand that lack of nutrition affects not only the decorative component of the bush - the harvest will also suffer from this. The fruits will not be so large and juicy, bitterness may appear.

Yellow spots on cucumber leaves

Diseases in which leaves turn yellow

The most serious cause for concern is yellowing due to diseases... Microorganisms and pests affect cucumbers when favorable conditions are created - thickening, high humidity, cold, heat, weakening of the root system. That is why it is so important to comply with the minimum care and prevention measures.

Note! The characteristic yellowness for a fungal disease is spotty.

What are the most common diseases in cucumbers?

  • Powdery mildew - the scourge of cucumber culture. Defined as red and whitish spots on the underside of the leaf. It starts spreading from the bottom of the bush. Plaque passes to the base of the stem. Greenhouse plantings suffer from powdery mildew more often due to high humidity.
  • Downy mildew, or peronosporosis. If the leaves in the upper part are covered with yellow spots, and in the lower part - with a white bloom, then one can suspect the presence of this fungal disease on the bush. Further, the leaf plate turns brown, dries and dies completely.
  • Fusarium. First, the tops, and then the leaves are covered with rusty spots, the whips wither and die off. Fusarium disease is best prevented, as treatment is difficult.
  • Anthracnose. The characteristic signs of the fungus are yellow-brown spots with an indistinct edge, covered with pink pubescence. On the stems and petioles of a plant in the neglected form of anthracnose, you can find oblong dents.
  • If a virus is infected, the bush cannot be cured. The plantings are uprooted and burned. That is why preventive measures are very important - tillage on the site and for seedlings, purchase of healthy seeds.
  • The foliage also turns yellow from exposure to parasites. When a whitefly appears on a bush, a spider mite, aphid or other insects, he begins to lose vitality before our eyes. The parasites feed on the juices of the leaf, stem, and sometimes attack the roots.

Cucumber tops dries up

Natural causes

When are there no reasons for concern?

  • When the plant grows ovaries and intensively nourishes the fruits, all substances are distributed to the upper half of the bush. For this reason, the lowest leaves turn yellow. The cucumber just doesn't have the strength to maintain its integrity, and that's okay. If no signs of the disease are observed, then you can not worry in vain, but sometimes inspect the bush.
  • If the bush is healthy and leafy enough, it evenly distributes its forces and can sometimes get rid of the lower leaves, since they still get less light.
  • By the end of the season, the leaves turn yellow and dry "from old age."

Growing cucumbers on trellises

Standard rules for crop care

The care strategy depends on the variety of cucumber and its placement, as well as the characteristics of the climate and soil. Gardeners have a few standard rules that work for most cucumber plantings. Among them are feeding, watering, protection from drafts, the formation of bushes and several other measures.

  • Soil moisture should be kept moderate. In hot weather, watering can be increased, in cold weather, it can be reduced.
  • Dry air in the greenhouse must be humidified.
  • Watering is carried out in the morning.
  • The soil is mulched to retain moisture and protect the root system from overheating.
  • In the open field, the culture requires special protection. If a decrease in temperature is predicted, all plantings are covered with spunbond or film.
  • Inspection of the bushes for fungus and pests is carried out as often as possible. At the first signs of illness, the gardener should immediately take action. This will save the bush and all neighboring plantings from death.
  • Observance of crop rotation is necessary - this way the risks of recurrent diseases are reduced.

"Overfilled" cucumbers need to be revived by loosening the soil and adding sand and wood ash to it.

Top dressing for cucumbers

How to feed "hungry" cucumbers?

It is better to bring food in the form of complexes, so as not to be mistaken in the dosages of one or another element. In a garden store, you can always purchase a special composition for cucumber plantings.

Standard feeding schedule:

  1. At the seedling stage, nitrogen fertilization is applied with the appearance of the first true leaf. These are ammophoska, azofoska, organic.
  2. With the onset of flowering, the plantings are fertilized with a complex with the main elements - nitrogen, phosphorus and potassium.
  3. With the advent of the harvest, the bush needs to be fed with microelements.

How to sprinkle and water cucumbers if their leaves turn yellow?

  • Herbal infusion. For 1 kg of grass, 10 liters of water is enough. Chop greens, pour over and insist for a week. Dilute the finished concentrate with water in a 1: 9 ratio. It is used for root watering and spraying on the leaf.
  • Root feeding option: add 10 g of superphosphate, ammonium nitrate and potassium salt to 10 liters of water.
  • 40 g of urea per bucket of water. Spray plantings over the leaf. Under the root, you can additionally add organic matter - rotted manure.

Oxyhom drug

How to spray for diseases?

Many summer residents prefer to treat common diseases of cucumbers using standard techniques and folk remedies.

  • With extensive damage, it is better to treat the bush with a fungicide or insecticide. Examples: Fitoverm, Aktellik, Aktara, Fundazol, Oksikhom, Tiovit Jet etc. It is necessary to use powerful drugs in protective equipment and strictly according to the instructions. You can not treat the bushes with chemicals during harvest. After treatment, at least 20 days should pass.
  • Potassium permanganate. Prepare a 1% potassium permanganate solution and spray the plantings with it. You can treat the bushes with a solution at the first signs of yellowness.
  • 1% solution of colloidal sulfur (40 g per 10 l) is a recommended remedy for anthracnose and powdery mildew.
  • Bordeaux liquid - 1% solution.
  • Copper sulfate is a spray solution with a concentration of 0.5%.
  • Onion infusion. For 700 g of husk - 10 liters of water. Boil and leave for 12-14 hours. Dilute the infusion with water in a ratio of 1: 4 and spray the bushes, as well as pour part under the bush.
  • Soda solution. 1 tbsp. l. substances per 1 liter of water.
  • Medical mixture for seedlings: for 10 liters of water - 1 liter of milk, iodine (30 drops) and 20 g of laundry soap grated into shavings (the component is needed to fix the substances on the sheet). Means with iodine - prevention of powdery mildew fungus. The acidic environment from milk also inhibits the development of pathogens.

Important: diseased leaves must be removed and burned.

So that the cucumbers do not turn yellow, it is enough for the gardener to properly care for them. But not always the weather and the nutritional value of the soil allows you to grow an absolutely problem-free culture. Another tip from gardeners: choose modern crop hybrids that are resistant to diseases and adverse conditions, and then there will be much less problems.

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