What to do if cucumber ovaries turn yellow in the greenhouse
Cucumbers are often grown in polycarbonate greenhouses, and many gardeners are faced with the problem of yellowed ovaries. There are many reasons why ovaries turn yellow. Therefore, before planting cucumbers in a greenhouse, you should familiarize yourself with possible errors during cultivation.
What to do, if cucumber ovaries turn yellow in greenhouses, we will discuss further.
For what reasons can cucumber ovaries turn yellow and wither in a greenhouse?
Causes of yellowing cucumber ovaries in a greenhouse can be divided into three groups: due to growing conditions, due to improper care, due to diseases and pests. Let's look at each of them in more detail.
Unsuitable growing conditions
These are environmental factors that adversely affect the growth and development of a plant. These include: lack of lighting, violation of temperature conditions, violation of humidity conditions and too dense planting.
Lack of lighting
Lack of light is one of the main reasons for yellowing of cucumber ovaries. Proper distribution of light will accelerate the growth of cucumber seedlings and increase the yield several times.
Failure to comply with temperature conditions
The temperature range that is most favorable for good growth is +18...+35°C, with daily temperature changes of no more than 6°C.
Important! At temperatures below +12°C, plant growth slows down, the leaves begin to turn yellow, and the ovaries begin to fall off.
Insufficient humidity
Cucumbers are necessary water twice a week, 25 liters of water per bush.If there is insufficient moisture, the roots take moisture from the stem and leaves, which causes them to turn yellow. Excessive watering also adversely affects the growth of cucumbers, so it is worth maintaining a balance and not flooding the soil.
Excessive cramped seating
When planting seedlings in the soil, correctly calculate the area for normal growth of each plant.
Important! The distance between seedlings should be 30-50 cm, adjacent rows are made at a distance of 80 cm from each other.
In the case of a denser planting, the roots of the seedlings will begin to intertwine underground as they grow and “rob” each other. Dense planting will lead to a lack of light and, as a result, wilting of the ovaries.
Do not forget about removing the lateral tendrils and shoots to strengthen the mother bush.
Improper care
A good harvest of cucumbers depends not only on environmental factors, but also on caring for the plant. Typical mistakes when caring for cucumbers include: irregular watering, violation of the mineral composition of the soil and insufficient pollination.
Irregular watering
A regular watering system is important for the growth of cucumbers. The soil should always be sufficiently moist so that the water saturates the soil and the roots grow deeper.
Water temperature is also important. Avoid watering with cold water as this may kill the entire crop.
Excess or deficiency of fertilizers
Violation of the mineral composition of the soil and excess fertilizer can adversely affect crop growth. Cucumbers need not only phosphorus, potassium and nitrogen, but also a full complex of all microelements.
To compensate for the deficiency, microfertilizers containing copper, molybdenum, boron, zinc and manganese are added to the greenhouse soil once every 3 years.If you are against “chemical” fertilizers, use regular wood ash.
Reference. The norm for using wood ash as fertilizer is 300 g per 1 m².
Incorrect pollination
Growing cucumbers in a greenhouse involves choosing self-pollinating varieties and hybrids. But even their ovaries can die from poor fertilization. The most common reason for this is poor ventilation in the greenhouse, which leads to air stagnation and the plants lose the physical ability to self-pollinate.
Diseases and pests
Typical diseases of cucumbers are bacteriosis, downy mildew, ascochyta blight, anthracnose, and sclerotinia. Among the pests, it is worth highlighting aphids and greenhouse whiteflies.
One of the most dangerous diseases is bacteriosis, which most often manifests itself in damp weather. The disease can develop due to excess air humidity in combination with dense planting. When bacteriosis occurs in cucumbers in a greenhouse, the leaves and ovaries turn yellow and the yield decreases.
You can recognize bacteriosis at the initial stage by noticing small polymorphic spots on the leaves. In damp weather, drops of cloudy liquid are visible on them - colonies of bacteria. When the damaged areas dry out, they crumble and crumble. As a result, the leaves become affected by small holes, and the flowers crumble and fade.
How to deal with it
To avoid the problems described above when growing cucumbers in a greenhouse, follow the necessary agrotechnical procedures.
Dropping
The method is used to protect the root system and normalize soil moisture. Its essence is that the roots and lower part of the stems are covered with a layer of moist soil, which transfers some of the moisture to the roots and protects them from the negative effects of external factors.
Stepsoning
Pinching is the process of removing stepsons from plants. By receiving nutrition from the soil, the plant distributes nutrients evenly among all its stems. The lateral shoots receive the same amount of substances as the fruiting clusters, depriving them of additional nutrition.
By removing these shoots, you will direct all the nutrients to the formation of a high-quality fruit.
Drying the soil
Excess moisture in the soil negatively affects plant development, reduces aeration of the root system and stimulates the death of root hairs. If you flood the soil, you should let it dry and not water the plants for several days.
Ensuring temperature and humidity
To ensure optimal temperature conditions, manure mixed with straw can be placed in the beds.
Reference. The recommended amount of a mixture of manure and straw is 4 kg per bush.
If the temperature drops sharply at night, place a dark barrel filled with water in the greenhouse. It will heat up during the day and release heat at night, maintaining a higher temperature and increasing air humidity.
Correct lighting
If there is a lack of lighting in greenhouses, phytolamps are installed. Lighting is organized as follows:
- bushes must be under lighting for at least 12 hours a day;
- there should be no interval between natural and artificial lighting;
- At night, lighting is not required, since cucumbers must be in the dark for at least 6 hours.
Trimming
Pruning is necessary to reduce the vegetative mass of the crop, which consumes a lot of liquid and minerals to feed it. After pruning, only the necessary parts of the plant remain, which receive more nutrition.
Important! Perform pruning early in the morning.Then within a day the “wound” will dry out and begin to heal.
Top dressing
When a plant has exhausted its supply of nutrients, it needs additional feeding. You can feed the bushes with solutions of the following products: “Mortar”, “Kemira”, “Master” and others.
Note. Hybrids and varieties with bunched ovaries most often suffer from lack of nutrition.
Watering
Water the cucumbers at the root with water at a temperature of +24°C. Before flowering and fruiting begin, it is necessary to maintain moderate humidity - the plants are watered no more than 2-3 times a week. After fruiting begins, cucumbers are watered every 2-3 days.
Pollination
Ventilate the greenhouse twice a day for at least one hour. Good air ventilation will prevent air stagnation and help plants self-pollinate. Dense planting of cucumbers negatively affects the quality of pollination and leads to a decrease in yield.
Treatment of diseases and getting rid of pests
To treat diseases and exterminate pests, folk and commercial remedies are used. The method is chosen depending on the type of lesion:
- Aphid. For the treatment of aphids, the drug “Inta-vir” works well - 1 tablet per 10 liters of water, or “Strela” - 50 g per 10 liters of water.
- Whitefly greenhouse Using 0.2% of the biological product "Actofit" 2-3 times during the entire growing season will help protect the greenhouse from whiteflies.
- Bacteriosis. To protect the crop from bacteriosis, you need to start from the seeds. The seeds are soaked in a 0.02% solution of zinc sulfate, dried and planted. If the disease appears on the leaves, they are immediately treated with Bordeaux mixture.
- Downy mildew. Sprinkle the soil with wood ash, and spray the plant with a solution of Fitosporin.
- Anthracnose. Cucumber bushes affected by anthracnose are removed, and to prevent the spread of infection, neighboring bushes are treated with a 1% solution of Bordeaux mixture or a 0.4% solution of copper oxychloride.
As an alternative to Bordeaux mixture, you can use folk remedies:
- Dissolve 1 liter of whey and 5 drops of iodine in 10 liters of water. Spray the plantings every 2-3 weeks. Make sure that the solution wets both sides of the leaves well.
- Fill a bucket of onion peels with warm water and leave for two days. Strain the resulting mixture and dilute it with clean water in a 1:1 ratio. Spray every 10 days from the beginning of flowering.
Preventive measures
To prevent yellowing of the ovary in the greenhouse, preventive measures should be followed:
- choose a variety suitable specifically for greenhouse cultivation;
- organize a place for planting cucumbers;
- pre-fertilize the planting site;
- carry out preventive spraying with a 1% solution of boric acid;
- observe the irrigation regime, use warm water;
- Regularly prune bushes and remove excess ovaries;
- monitor weather conditions and ensure optimal temperature in the greenhouse;
- harvest in a timely manner.
Conclusion
By following the recommendations for organizing lighting, temperature and humidity conditions, and planting density, you will create favorable conditions for the normal growth of cucumbers. Proper plant care and pest and disease control will not only minimize possible crop loss, but also increase the yield of the final product.