Why do the leaves of cucumbers turn pale

Why do cucumber leaves turn pale? Many gardeners are faced with such a problem. Consider the main causes and solutions to the problem.

Causes of pale leaves of cucumbers

Lack of minerals

One of the main reasons why the leaves of cucumbers turn pale is the lack or, on the contrary, an excess of some minerals and trace elements in the soil.

Basically, the violation of this balance affects the quality and presentation of the fruit, and also worsens the growth of bushes. Leaves turn white most often due to a lack of nitrogen, magnesium, iron, calcium, phosphorus, potassium, copper and manganese.

Nitrogen

The lack of this element affects not only the pallor of the foliage, but also the development and modification of the whole plant:

• laterally formed lashes and leaves;
• the inflorescences fall;
• a green ovary does not form;
• yellow spots appear on already mature leaves.

Leaves turn pale, later become yellowish, then completely darken. The very first fall sick leaves from below. An insufficient amount of nitrogen can be recognized by green veins on the leaves. They retain their color almost until they fall.

Treatment

Nitrogen supplements must be applied to the soil in a timely manner. You can also fertilize mullein with water (1 l of mullein per 10 l of water), 1 l for each plant.

Magnesium

You can recognize the lack of magnesium by the following the signs

• the leaves turn pale below;
• the plant stops growing.

The first signs of blanching are visible between the veins, then closer to them, and then color spreads throughout the plant. After that, the cucumbers acquire a purple or maroon color at the edges of the leaf plates.

Treatment

The plant needs constant foliar dressing with magnesium nitrate in the ratio of 100 g of the drug per 10 l of pure water.

Iron

When not enough iron plant needs root dressing with iron sulfate

With a deficiency of this mineral, the rate of photosynthesis decreases. Also, the plant (especially young) loses color, starting from the top. If you do not fix the problem in a timely manner, this will entail:

• drying of the leaves along the edges;
• cessation of growth of the young leaf.

Loss of green color begins soon in mature leaves. Lack of iron does not affect the yield and fruiting quality, but the growth and flowering of the bush slows down.

Treatment

The plant needs root dressing with iron sulfate (5% solution) or foliar fertilizer with soap and water from an ash extract.

Calcium

Mature leaves do not respond to a lack of calcium, unlike young leaves that have a deep dark color. With a lack of calcium:

• the foliage turns pale stripes;
• bends down.

Treatment

foliar application 3 % solution of chelated calcium.

Phosphorus

With a lack of phosphorus:

• dry spots form on the lower leaves;
• the bush slows down in growth, or even completely ceases to grow;
• the ovary and flowers crumble.

Treatment

Phosphorically drip irrigation potash fertilizer.

Potassium

If it is noticeable that a light border has formed on the leaves and the shoots have quickly faded, the plant has potassium deficiency.

Treatment

The leaves are treated with a soap solution with the addition of potassium permanganate (5%). They also water the plants with ash solution (1 tbsp. Ash per 10 liters of water) with the calculation of 1 liter of prepared solution for one plant.

Copper

A lack of copper adversely affects the plant

When the deficiency of copper leaves noticeably fade, shoots fade, and the flowers quickly crumble even before the formation of the ovary. It all starts with light green, and then almost colorless tops of the leaves.

Treatment

Leaf treatment with copper sulfate (5%) during the growing season. Also for prevention, in the spring, at the place where the cultivation of cucumbers is planned, a solution of the same copper sulfate (1%) is added to the soil, which also helps in the fight against different types of fungal diseases.

Manganese

With a deficiency of manganese:

• bright dot spots appear over the entire surface of the leaves;
• the tissue near the veins begins to yellow;
• the edges of the leaves turn orange or even rusty.

Treatment

The plant needs root dressing with a solution of manganese in a ratio of 3 mg per 1 liter of water, under each bush.

Frostbite

It happens that after the onset of sudden frosts, blanching of the leaves or their complete discoloration is noticeable.

Sometimes this happens not on the entire surface of the sheet plate, but only on its individual parts. These pale spots are similar to water stains, sometimes lighter or darker.

Treatment

Remove all leaves that have been damaged, as well as the most affected shoots, if any.

Diseases

The most commonly affected diseases are cucumbers in the greenhouse. Humidity only contributes to the spread of both viral and fungal infections.

It is necessary to constantly air and harden the seedlings.

Mosaic disease

Sick leaves need to be removed

The disease affects both greenhouse cucumbers growing in open ground . A pale yellow dotted pattern forms on the leaves, after which the leaves curl and the edges tuck. The reason for the spread is the planting of the infected seed.

Treatment

You can get rid of the disease only by removing the infected area of ​​the plant. The rest, not yet infected, sprinkle with non-fat milk (1%). It is advisable to burn infected bushes away from the garden.

Powdery mildew

A whitish bloom forms on the leaves, resembling lime stains. The disease affects cucumbers growing in the open ground. Most often, the first signs appear after rain or when damp. Plaque can cover not only cucumbers, but also other crops growing nearby.

Treatment

They treat the bushes with mullein and urea (the proportion of the solution is 1 x 50).

Peronosporosis

Symptoms of the disease are similar to powdery mildew, but a yellowish coating is on top of the leaf, below it is gray. If measures are not taken in a timely manner, the spots will darken, and the leaves will become deformed and dry. Causes may be uneven watering, temperature changes, cold water.

Treatment

Watering should be limited or even stopped. All damaged leaves are completely removed, and all bushes are treated with Oxychom. The solution is prepared in a proportion of 2 tablets per 10-12 liters of water.

Root rot

This type of fungus first affects the roots and then the lower part of the plant, and then rises . The leaves turn pale, and then the entire vine grows dead.

The cause of the disease is uneven watering, planting density, which causes rapid infection, as well as increased humidity (in the greenhouse).

Treatment

Root rot can kill all plants

The pale leaves should be removed, and the affected bushes should be treated with the Infinity 61 SC solution.

White rot

White rot – another reason for the pale leaves of cucumbers. The first sign of the fungus is the appearance of jelly-like wet spots near the roots, on which white fluff soon appears. The fungus spreads throughout the plant, affects the shoots, and then the leaves.

Treatment

First, the infected areas are removed. When the affected part of the bush is not very large, it is sprinkled with a mixture of crushed chalk with lime. Plants that are completely affected by the disease are removed.

Pests

Pests also often cause pale spots on cucumber leaves.

Spider mite

First, the leaves of the cucumbers turn pale, then turn yellow, then dry. A cobweb is visible at the bottom of the leaf.

Treatment

Treat with a decoction or infusion of dandelions and wormwood. You can also use drugs:

• “Actellik”;
• “Fitoveri”;
• “Acaricide”;
• “Agavertin” .

Thrips

The affected parts of the cucumbers, after turning pale and lost color, die.

Treatment

Spray with a strong infusion of onion, and then treat:

• with “Actara”;
• “with a ram”;
• “Karbofos”;
• “Decis”;
• “Celion”.

Nematodes

A specifically pale surface of leaves with yellowness, which is also characterized by deformed parts of the bush, most often dwarfism.

Treatment

The affected plants are best destroyed. To protect the bushes that have not yet been affected, they use formalin solution or 96% Bordeaux liquid.

Watering mode

The reason the leaves turn pale in cucumbers may be a lack of moisture in ground or use of cold water for irrigation. It is necessary to create a regular schedule of irrigation using settled and warm water.

Ovary excess

O Romney pulls ovaries number of plants all the vital forces, as a result of cucumber bushes become lethargic and lose their color saturation. They harvest a certain number of fruits, distributing them evenly over the vines, according to the principle of decreasing, up.

Conclusion

The problem under consideration may be due to an excess or lack of minerals, lighting mode and watering, with diseases and pests, or with an unsuccessful selected seed variety. A good option is to choose a complex fertilizer that provides protection to cucumbers, as well as taking care of the required number of trace elements in the soil.Prevention of pests is also carried out in advance to get a healthy crop.