If it becomes obvious that greenhouse cucumbers are not getting proper development, emergency measures must be taken before the situation gets out of control. In order to draw up a rescue plan, it is important to establish the cause of the negative phenomenon.
It is not for nothing that cucumbers are considered a whimsical crop, because a number of agrotechnical errors can lead to the lack of the expected harvest. These difficulties lead to the fact that many amateurs completely refuse to breed this culture. However, purposeful owners of private plots methodically comprehend the technology of growing greenhouse cucumbers, achieving the most optimistic results.
Poor soil composition
The fertile composition of the soil dries out over time, which becomes the main reason why cucumbers do not grow in a greenhouse. The main thing that needs to be done for this is to systematically replenish the composition of the soil with special additives. A complete renewal of the soil composition is carried out every 3 years. To do this, it is necessary to remove the top layer to a depth of about 25 cm, replacing it with a fresh composition enriched with humus, sand and peat.
It also happens that after flowering, young fruits successfully set up, but instead of the expected development, they suddenly begin to dry out and fall. This suggests that plants need periodic feeding, especially if you have to deal with infertile soil. In this case, the first top dressing is carried out immediately at the time of planting seedlings.
To do this, humus or peat diluted with the ground is added to the planting holes.
Unsuitable conditions
If the planting is too dense, the plants have to compete, which significantly reduces the rate of their development. As a result, they not only grow slowly, but sometimes completely disappear. Insufficient ventilation or poor lighting can adversely affect the quantitative indicator of the yield. These reasons are eliminated by the regulated nature of planting, when 20 cm is maintained between the shoots, and 60 cm is left for the inter-row space.
Another important condition for the full development of culture is temperature control. The optimal difference between day and night air temperatures should be +25 and +15 degrees, respectively. If the temperature drops below +15 degrees, the plants will suffer from slow growth and poor ovary formation. In addition, the fruits can take a distorted (twisted) shape. If the temperature exceeds the limit of +30 degrees, the fertilization process will be disrupted, and the ovaries will stop forming.
Fertilizer shortage
Lack of fertilizer can cause the seedlings to die, and the planted plants to wilt and not develop. If this did not happen, and all the sprouts after planting were well accepted, you should not stop feeding so that growth does not stop. Sometimes even successfully adopted cucumbers subsequently die.
The most effective feeding system is considered to be the periodic alternation of the varieties of introduced elements. The main emphasis is on the ratio of nitrogen to phosphorus in the soil.
You should know that an excess of the nitrogen component leads to the active development of the tops, and the plant does not have the strength to fully bear fruit. The leaves become bright green in color and differ in their size. But the activity of the formation of ovaries is noticeably reduced, most of the flowers bloom in vain.
A high nitrogen content is accompanied by a lack of phosphorus, as well as potassium, which are necessary for the plant to form and develop fruits. At each stage of development, the plant needs a certain composition of top dressing, depending on the current growth phase.
Root
For feeding the roots, either dry mixtures or liquid substances are used. Dry mineral compositions must be applied to the soil during the period of mass processing – after the winter frosts are gone, as well as at the time of planting, adding a small amount to each hole. Liquid solutions are much more effective to use during the period of active development of the plant, due to the ability to quickly assimilate. When applying top dressing, you should rely on the instructions and advice of gardeners on a specific preparation.
Foliar
Foliar top dressing allows you to maintain the vitality of the plant during periods of transition to the next phase of development. They are produced at the stage of active growth, at the time of flowering, as well as at the fruiting stage. This enhancer improves both the efficiency of growth and the ability to form and develop fruits. Irrigation is carried out at a consumption of 100 ml of the active composition per 1 m2.
Salt spots, which as a result can settle on the foliage, should be carefully removed.
Treatment of diseases
Various diseases caused by pathogenic fungi can lead to serious difficulties in the development of cucumbers. The fungus lives and develops in the soil, from where it subsequently attacks the plant. The uncontrolled development of fungal organisms leads to the destruction of the culture.
Cladosporiosis
To prevent plants from being affected by this disease, it is recommended to take measures to prevent the spread of the pathogen. For this purpose, some recommendations should be followed:
ensure systematic ventilation of the greenhouse;
do not leave plant residues on the beds;
do not use cold water for irrigation and sprinkler technique.
When the first signs of the disease appear, it is necessary to suspend watering for a period of 5 days. During this period, plants are treated with a 0,4% Bordeaux mixture or copper oxychloride with a XNUMX% content.
Root rot
To prevent the development of root rot, the following conditions must be created:
observe the regulated distance between crops;
timely remove the remains of plant mass from the soil;
avoid watering with cold water.
At the first signs of the onset of the disease, it is necessary to take measures to stimulate the development of new root processes. For this purpose, fertile soil 5 cm deep is sprinkled on each plant. This will allow the cucumbers to take root again.
Mučnistaâ rosa
You can prevent the development of this disease by taking the following measures:
collect fruits and plant residues in a timely manner;
disinfect the greenhouse after harvesting using a formalin solution;
keep the air temperature within 25 degrees;
provide irrigation with warm water;
use powdery mildew resistant hybrids.
At the first signs of the onset of the disease, it is necessary to treat the plants with a solution of copper oxychloride. For its preparation, 40 g of a concentrated mixture diluted in 10 liters of water is used. And you can also use colloidal sulfur, it is also diluted 40 g in 10 liters of water.
Pest Control
Various insecticides help organize pest control. In their absence, you can use the practice of using folk remedies.
For this purpose, a soapy solution, a decoction of onion peel or tea leaves from garlic arrows may be suitable.
greenhouse whitefly
The first measure of protection against this pest is a mosquito net, which must be installed on the windows and doorways. In addition, it is necessary to monitor the absence of weeds in the soil.
If an insect has been seen, traps should be resorted to. For this purpose, a piece of plywood is painted with white paint, and after drying, it is lubricated with petroleum jelly (you can use castor oil). As an additional preventive measure, you can periodically wash the leaves of cucumbers from below, where the whitefly strives to place its masonry.
Melon Caviar
This type of pest spreads mainly through weeds. This means that the first measure of salvation will be their absence in the beds. Tobacco and hot pepper tea leaves are used as an active agent to counteract aphids. In this case, 200 g of tobacco is mixed with 30 g of chopped pepper pods, poured with hot soapy water (10 l) and insisted for a day. And you can also use another mixture when 2 cups of ash are poured into 10 liters of hot soapy water. This composition must also be insisted for a day.
Preventive measures
To avoid damage to the root system when planting seedlings, you can plant seeds on pre-prepared beds. And also for seedlings, individual dishes are often used, from which the plant is transplanted along with the ground.
It is necessary to remember about the additional feeding of plants during the appearance of ovaries, which are in great need of nutrients. Fruit picking is best done in the morning or evening. Fruits not harvested in time will overripe and prevent the development of new formations.
Excessive vegetative mass also hinders fruit development by diverting nutrients for its own maintenance. Extra leaves are removed, which also reduces the degree of darkening, which poses a threat to young ovaries.
