Reasons why cucumbers turn yellow in a greenhouse

It happens that a greenhouse plant, its leaves and fruits begin to turn yellow. To get a good harvest, you need to look for the root cause and eliminate it.

The reasons can be several:

1. Sudden temperature changes, low average daily temperatures, frosts.
2. Lack of minerals in the soil.
3. Violation of irrigation technology.
4. Plant overload with ovaries.
5. Incomplete pollination.
6. Damage by insects, fungal infections.

Violation in care

The most optimal temperature in the greenhouse should be 22-26°C. Under such conditions, it is easy for a plant to obtain nutrients in the rhizomes. When the temperature drops to 14°C, the seedlings turn yellow and stop growing, and die at -1°C. To warm the plant and protect it from freezing, it is necessary to use artificial materials, films or special coating materials, such as Spandbond, Lutrasil, Agrotex. You can put bottles of hot water. To prevent further disease, the plants are removed from bad flowers, leaves, treated with a solution of manganese, and then sprayed with a solution of copper sulfate.

When the soil is poor in minerals and trace elements, the plant turns yellow, withers, and stops growing.

Light green spots on the foliage indicate a lack of magnesium, and yellow – a sign of potassium deficiency. At first, lighter, and then yellowed and twisted leaves, crooked, hook-shaped fruits indicate a lack of nitrogen in the soil. Cucumber seedlings a few days before planting in greenhouses should be sprayed with a solution of trace elements and fed with fertilizers.

In autumn and spring, when digging the soil, it is necessary to introduce rotted manure into it, this will increase the nitrogen content in it. Both a lack and an overdose of mineral fertilizers can lead to yellowing of cucumbers in a warm garden. So you need to carefully read the annotation and follow the instructions exactly when using industrial mineral fertilizers.

This vegetable is very fond of moist air and soil. Therefore, poor watering can provoke yellowing of the plant. Greenhouse cucumbers require frequent and deep watering with warm settled water. Cold water also provokes yellowing of the leaves. Deep soil moisture is required for the full development of the root system. During fruiting, it is necessary to increase the amount of watering. Inconsistent and poor-quality watering will badly affect the embryos and fruits of the cucumber.

Cucumber diseases

Some diseases can cause yellowing of foliage and fruits:

1. Fusarium wilt can lead to the death of the plant. The fungus produces toxins that completely block the supply of nutrients to the leaves, embryos, fruits and stems. The land in greenhouses should be immediately replaced, and the vegetable variety should be changed in subsequent years.
2. Mučnistaâ rosa – a fungus that is manifested by the appearance of small light spots, then they slowly spread over the entire surface. A white or reddish coating forms on the surface of the leaf plate. Then the leaves and embryos turn yellow and dry. To prevent the disease, it is necessary to cultivate the land in the winter garden before planting with a solution of manganese or green manure.
3. Root rot It is formed as a result of improper moistening of the plant and non-compliance with the temperature regime. When watering with cold water, with a sharp cold snap, the rhizomes begin to crack and the leaves remain without nutrition, begin to turn yellow and wither. The diseased plant is removed along with the diseased soil. Crushed coal, ash is introduced into the soil, sprayed with a solution of copper sulfate.

Insect parasites can spoil the development of plants:

1. spider mite – a pest that appears on the inside of the leaf and spins a small web. Breeds in warm conditions. Exterminated by special chemicals.
2. Melon Caviar threatens the fruits of the entire period of fruiting. Lives on the inside of the leaf and feeds on its juice. Moves from weeds. To get rid of, weed the beds and destroy the weeds. Sprayed with infusions of tobacco and capsicum, soapy water.
3. greenhouse whitefly also a weed pest. Causes wilting of leaves. It is necessary to destroy weeds, spray the plant with ordinary water, loosen the soil and fertilize it with peat, sawdust and humus. You can make sticky traps to which insects will stick.

Many ovaries and lack of pollination

A large number of cucumber ovaries in a greenhouse can lead to underdevelopment of fruits, the embryos will stop their development, turn yellow and rot. A sufficient number of ovaries on the stem is about 25-30. Excess shoots and ovaries must be removed.

Some plant varieties can only be pollinated artificially. It is necessary to ensure access of insects to greenhouses. To do this, the doors should be open during the day, subject to warm weather conditions. To attract bees, you can spray flowers with special products or natural compounds, such as sweet water – 1 tbsp of sugar or honey per 2 liters of water, or 0,5 g of boric acid per 1 liter of water. Also, for the next seasons, it is worth planting such honey plants in cucumber greenhouses – borage, dill, etc. This is why cucumbers turn yellow.

For various reasons, cucumbers turn yellow in the greenhouse, what needs to be done is to eliminate the cause in a timely manner. You can use at least folk methods, even the latest chemicals. The main thing is to properly care for and grow plants. Then you will have a rich harvest.