Quite a lot of vegetable growers grow cucumbers in a polycarbonate greenhouse. However, many of them face a problem, which is that the cucumber leaves turn yellow. Before processing cucumbers, you need to decide why the leaves of cucumbers in a greenhouse turn yellow and watch a video that describes ways to solve this problem. This is the only way to get rid of yellowed foliage and protect the plant.
Causes of yellowing
There are different reasons for the yellowing of leaves in cucumbers grown in greenhouse conditions. It is recommended that you familiarize yourself with them in advance in order to better understand how to deal with yellow leaves in the future.
Improper watering
Quite often, leaves on bushes turn yellow in a greenhouse due to improper watering. It is no secret that cucumbers are moisture-loving vegetables, but this does not mean that they need to be watered very often. Particular attention should be paid to watering before fruiting. During this period, soil moisture should not be too high. It is precisely because of the large amount of moisture that yellowing of the leaves may appear.
Another reason why the edges of leaves turn yellow is watering with too cold water. If the temperature of the liquid is below room temperature, the leaves of the cucumber seedlings will begin to dry out.
A considerable number of vegetable growers grow cucumbers in open ground. In this case, it is necessary to pour water under the stem. Spraying bushes in the sun can cause burns on the leaves. Cucumber seedlings should be watered early in the morning or evening to avoid sun exposure.
Bad light
Sometimes the leaves turn yellow around the edges due to the fact that they are grown in rooms with insufficient light. Poor lighting not only causes the leaves to dry out, but also negatively affects the overall growth and development of the bushes.
It is recommended to plant cucumbers according to a special pattern, with the help of which the plants will not shade each other. To prevent the leaves from turning yellow, you need to plant the bushes at a distance of at least 80 cm.
There are times when seedlings' leaves turn yellow at the edges due to too much light. Most often this happens in the summer, when the sun can not only warm the plant, but also burn it.
Unstable temperature
No gardener is immune from sudden temperature changes. That is why cucumber leaves turn yellow and dry out due to unstable temperature conditions. Even a greenhouse room is not protected from this problem, since night frosts can cause the temperature in the greenhouse to drop sharply.
To eliminate yellow leaves, you need to take care of additional protection of cucumbers at night. For example, they can be covered with special materials, which include spunbond or agrotex.
Also, the edges of the leaves of cucumbers in the greenhouse turn yellow due to low soil temperatures. It is recommended to grow bushes in soil that is heated to 20-25 degrees. At lower rates, the probability of leaf drying increases several times.
Soil composition
Problems with cucumber leaves can occur due to the poor quality of the soil in which they are grown. When growing cucumbers, it is recommended to use moist and loose soils that drain water well. It is also worth taking care of the nutrients that many plants need. If their number is not balanced, the leaves may become covered with yellowish spots.
Most often, an imbalance of minerals appears due to very frequent watering, which can wash out all the important components from the soil.
Poor pollination
Another reason why leaves may begin to turn yellow is poor pollination. This problem most often occurs in plants grown in greenhouse conditions. To prevent the leaves from drying out, you need to periodically ventilate the greenhouse. This will allow insects to get inside and start pollinating the bushes. You can also use a product such as Ovary or Bud to form ovaries.
Diseases
Sometimes yellow leaves appear on cucumber bushes due to various diseases. Most often, this vegetable suffers from bacteriosis, tobacco mosaic, ascochyta blight or downy mildew. So that these diseases did not harm cucumbers, it is necessary to engage in their prevention. To do this, all plants should be treated in advance with special biological preparations that are absolutely harmless to animals and people.
If the plant is already infected and its lower leaves turn yellow, then the yellowed foliage is treated with Bordeaux mixture. Bushes affected by bacteriosis or mosaic are not treated and therefore need to be gotten rid of immediately.
Pests
Quite often, mites and other insects are the reason why cucumbers turn yellow. When growing cucumbers, it is recommended to take preventive measures that would protect the bushes from certain pests. To do this, you need to regularly treat the plants with Funafon, Actellik and Aktara.
Ways to fight
Having decided why cucumber leaves turn yellow, you need to familiarize yourself with what methods are used to combat this problem. This is the only way to find out what to do if the leaves of the cucumbers in the greenhouse turn yellow. Various drugs are used to combat yellow leaf.
Aktara
This product belongs to the group of neonicotinoids, which are used to control many pests. Therefore, it is recommended to use it if the plant has turned yellow due to pests.
Aktara is applied immediately after the first insects appear on the bushes. To do this, you need to prepare a working solution consisting of a liter of water and 20-30 ml of the drug.It is recommended to use the mixture in the evening and in the morning, when there is still no strong wind and sun outside. In windy weather, you should not use the drug so that it does not accidentally get on other plants.
The product is very effective, since literally half an hour after its use, insects stop feeding and begin to gradually die.
Magic capsule
If the leaves turn yellow due to decay products that have accumulated in the soil, then you should use a Magic Capsule. With its help, you can restore the soil ecosystem and cleanse it of various toxic elements. The preparation contains a large amount of nitrogen, which can accelerate the growth of bushes several times. This product is also often used to treat weak and thin seedlings.
To prepare the solution, one capsule is diluted in 40-50 liters of water. In this case, the prepared mixture should infuse a little. You need to water the bushes with liquid 2-3 times a week until the soil ecosystem is completely restored.
Clonex
If the edges of the leaves begin to turn yellow, you should use Clonex. With its help, you can not only protect the bushes from diseases and pests, but also strengthen the tips of the leaves. All this is possible due to the fact that the drug contains quite a lot of vitamins and other useful components. The drug should be used once a week.
Glyocladin
Glyokladin is used if cucumbers turn yellow due to fungal infections. It was released specifically to combat pathogens of fungal diseases on cucumbers and other plants. To prepare the working mixture, you need to dissolve one tablet in a liter of water. The resulting solution is added to each bush that needs treatment.
Maksim
To protect cucumbers from diseases and insects, you can use the fungicide Maxim. This drug is one of the most effective means in the fight against late blight, rhizoctonia and other diseases that may be accompanied by yellowing of cucumber leaves. This fungicide is universal, since it can be used to treat almost all plants.
Before using it, you must prepare a working mixture. To do this, 4 ml of the drug is mixed with two liters of water, after which the liquid is infused for 30-40 minutes. After this, the mixture can be used to spray the bushes.
Folk remedies
Also, to combat yellowing of foliage, many use various folk remedies.
Pepper
Many folk remedies are prepared from various vegetables. In this case, the main ingredient for preparing the mixture is capsicum. 40 g of vegetables and 150 g of tobacco dust are mixed with a bucket of boiled water. Then the liquid is infused and filtered for 12 hours. After this, wood ash and liquid soap are added to it. The resulting mixture is very effective against mites or aphids.
Baguette
Some vegetable growers even use a loaf of bread to combat yellow leaves. You can make a mixture from it that will help get rid of fungal infections. To prepare the solution, a loaf of gray bread needs to be soaked for 24 hours in 10 liters of water. In the morning, add a little iodine to the container with the liquid. The mixture is thoroughly mixed and distributed into liter jars. Before spraying, one jar of liquid should be added to a bucket of water, mixed and used to treat the bushes.
Milk serum
This mixture is very effective in combating fungal diseases that can harm cucumber leaves. It is recommended to use it immediately after the first signs of the disease appear. To prepare a working solution, you need to add 2-4 liters of whey to 10 liters of water. All this is thoroughly stirred and infused for half an hour. Then 100 g of sugar is poured into the liquid, which is needed to improve the formation of new ovaries.
Conclusion
Many people don’t know what to do when the leaves on cucumbers in a greenhouse turn yellow. To do this, you need to familiarize yourself with the reasons for this problem and watch photos and videos that describe in detail the process of processing cucumbers.
