The gardening season is not only the joy of the harvest, but also some hassle.
Consider why yellow cucumbers in the greenhouse and what to do with it.
- Lack of fertilizer in the soil
- Too low temperatures for growing
- Mistakes when watering a plant
- Lack of light
- A large number of ovaries on cucumbers
- Too thick landing
- Diseases of cucumbers
- Pests that cause yellowing and wilting of cucumbers
Lack of fertilizer in the soil
The soil in the greenhouse can be poor in mineral compounds, which provokes yellowing.
With a lack of nitrogen sheet first brightens, and then change the color of his vein and all the gaps between them. For an adult plant, the symptom of "nitrogen deficiency" will be the appearance of deformed (hook shaped) fruits.
Experienced gardeners know how important it is to stick to a balanced dressing. If you add a lot of superphosphates, potash compounds or wood ash, then the nitrogen is not enough.
As a preventive measure when digging up the site, manure is applied at the rate of 2 to 3 buckets per 1 sq. M. Seedlings should preferably be treated a couple of days before planting - they are sprayed with mineral solutions or fertilizers are applied, calculating the dosage.
As they grow, the "diet" also changes. During the fruiting period, ashes and superphosphates are added, it can be fed with a mixture of mullein and grasses. Yes, and in the shops you can buy complex feeding for this particular period.
Too low temperatures for growing
Another reason why the ovaries of cucumbers turn yellow, which is particularly relevant for owners of film greenhouses. In warm weather, they warm up well, and at night they can overcool (remember the risk of repeated frosts).
For soil, optimal numbers are from +25 to +30 ° С. To do this, lay manure mixed with straw (but not more than 4 kg per bush). +13 - 15 ° С are considered dangerous, such conditions are critical for the plant.
Mistakes when watering a plant
Cucumbers are very demanding of moisture. Regular watering is required, otherwise you will have to face the problem of why the cucumber ovaries dry out.
There are a few simple rules to follow when watering:
- use warm water, about the same temperature as the soil (we exclude cold water, it will only accelerate the death of the ovaries);
- inspect the leaves and, if necessary, moisten the plants;
- it is not necessary to pour under the root (this will lead to rotting of the root);
- the soil should dry out;
- moisturizing combined with feeding a small amount of fertilizer.
Lack of light
Natural light is used to the maximum, but sometimes this is not enough. Its deficit is another facet of the question why cucumbers do not grow in the greenhouse.
Additional lighting also has its own principles:
- If stable cloudy weather has been established, the "additional illumination" is used even when the first shoots appear.
- Bushes should receive light no less than 12 hours a day.
- Time podgadvayut so that between artificial and sunlight there was no interval.
- Remember that the plant is also important darkness (at least 6 hours a day).
- If you are going to buy a phytolamp, keep in mind that for different periods different waves are needed. 400 - 500 nm (blue spectrum) suitable for the vegetative growth stage. For flowering using the equipment of the red spectrum, calculated at 600 - 700 nm.
Another moment - accuracy of planting and "neighborhood" with other cultures. Modern hybrids with their developed rhizome are planted, selecting 1 square meter for two plants. Nearby species should not obscure the cucumber.
A large number of ovaries on cucumbers
Having bought seeds with the mark F1 on the package, get ready for the next one. Hybrids thus indicated with proper care grow quickly, and more than a hundred ovaries can appear on a single plant.
They will have to pinch - A normal harvest can be removed if the ovaries were 20-25. The extra will interfere, which will have a bad effect on the shape of the fruit.
It is worth recalling about modern varieties. Branched species and lines with insect pollination, apart from the stem, also produce side shoots. For them, pinching is carried out above 5 - 6 leaves.
Parthenocarpic varieties most often grow in one stem, and for them the technology looks like this:
- we put a tapestry or rod, to which we tie the main stem;
- up to a height of 45-50 cm, all ovaries and flowers are removed together with the shoots;
- at heights from 50 cm to 1 meter from the surface, each lateral whip is pinned above the first leaf, and the ovary and a couple of sheets will be saved;
- from 1 to 1.5 meters: shoots are left in 3 - 4 nodes, the same applies to two ovaries, as well as a pair of leaves.
Too thick landing
Landing density also matters. Depending on the variety between saplings, they maintain an interval of 30 - 50 cm. About 0.9 - 1 m is left between the rows.
It is not recommended to “populate” seedlings - over time, the roots will begin to interfere with each other, and the grown up seedling will receive a little light.
Diseases of cucumbers
This culture is also subject to different ailments. Briefly describe what diseases are found in the "booths", causing yellowing.
Downy mildew, or perinosporosis, has recently become almost an epidemic. Risk factors are over-humid air, too frequent planting and sudden temperature changes.
First, yellow and light spots appear. Over time, they merge, acquire an oily shade and turn brown. If a brownish patina is visible on the inside of the plate, this is also a sign of illness. Its danger is manifested in the rapid current; within a few days, such dew will “devour” the whole plant.
Just seeing the first signs, immediately stop watering and fertilizing (for a week). When there is no moisture, treat the affected areas with drugs such as Oxy and Topaz. The solution should be heated to + 23 - 24 ° С.
It happens that the yellow tint appears already during the appearance of the ovary. This "worked" fusarium fungus. Once inside the plant, it blocks the course of nutrients, which can lead to the gradual death of the stem.
It is difficult to fight this infection, therefore prevention is important - alternating varieties and replacing affected land.
Pests that cause yellowing and wilting of cucumbers
The most frequent of the unwanted "guests" of the greenhouse is spider mite The insect is located on the lower side of the leaf, where it gradually pulls out the juices,covering the process itself branched web.
To remove it, the infected places are sprayed - there are many solutions in the shops. If you don’t have one on hand, the soap solution will come off. From folk remedies infusions based on dandelion, celandine or yarrow.
With regular soil digging, the risk of this pest is somewhat reduced - it overwinters at shallow depths and may die on the surface.
The same "scheme" and aphids. She can disturb the gardener all season (with a peak in July - August). Does not tolerate nitrogenous compounds, infusion of tobacco and soap solution.
From other means mention onion solution. 80 g of shallow "poppy" is added to 10 liters of warm water. After daily sludge infusion ready. You can take and garlic - the same amount of it will need half as much.
Small worm nematode dangerous for its speed, it quickly masters all the tissues. Ordinary spraying may not give the expected result, because the worm leaves the root soil.From preventive measures - the same digging, replacing the soil, its treatment with steam. In winter, the land is better to freeze.
We figured out why the cucumber ovary falls down. We hope these tips will help our readers to practice, and the greenhouse will delight the harvest.