Cucumber brought to us from India has become the most popular vegetable worldwide. Both adults and children love him. Not a single summer salad, not a single winter feast can do without it. So what should every self-respecting gardener know about the technology of growing cucumbers in a greenhouse?
Which greenhouse is better?
Spring is an unpredictable time of the year: today the sun is shining, and tomorrow it can snow. And for young immature plants, stability is so important! To achieve this just help greenhouses. How to choose a material for covering a greenhouse? At the peak of popularity, glass and cellular polycarbonate. They hardly differ in price, but they differ greatly in quality.
Glass greenhouse will let direct sunlight pass, and polycarbonate creates a soft diffused light that cannot destroy cucumbers. Accordingly, the costs of growing will not be lost. Cucumbers in a polycarbonate greenhouse will be safe even in winter, as this material is very durable and able to withstand snow drifts. It is worth noting that heating a glass greenhouse will take 10 times more energy than heating a greenhouse of polycarbonate of the same size.
Varieties or hybrids
Most varieties grown in hotbeds are hybrids (labeled F1 as seeds). For greenhouses, it is advisable to choose self-pollinated plants, as bees and other insects are reluctant to fly into such a building.
Since the lighting of the greenhouse for growing cucumbers in winter is very important, but often it is not enough, breeders brought out a sufficient number of early ripening hybrids. They will not suffer from a lack of sunlight and a sharp temperature difference in the winter. We list the main ones: Arina, Ladoga, Danila, Rossiysky, Northern Lights and others.
For the cultivation of cucumbers in the summer, the following varieties and hybrids, loved by summer residents, are suitable: "Emelya", "Hercules", "Pomegranate", "Manul".
Optimum temperature
The conditions for growing cucumbers in a greenhouse should be close to the climate of their homeland. For good growth and fruiting, it is advisable to use a temperature range from 24 to 27 degrees during the day. Maximum daily temperatures from 30 to 35 degrees are acceptable, but their long periods can adversely affect the quality of cucumbers.
Night temperatures not lower than 18 degrees provoke rapid growth and earlier ripening of cucumbers. At 12 degrees pace, they will grow more slowly, and the crop will be late.
When growing cucumbers in a greenhouse in winter, you can not do without a large number of sources of artificial heat and lighting. In this case, use lamps for greenhouses, underground heaters. To protect cucumbers from cold gusts of wind and snowstorms, warming the walls of the greenhouse will help with foam or other materials intended for this. To save heat and to avoid a sharp hit of cold air inside when opening the door will help a small extension in front of the greenhouse.
Soil is an important component
Good soil for greenhouse cucumbers should be well-drained at least 48 cm deep. Soil should be used with a low content of soluble salts and without disease. Sandy loam is preferable to sand or clay.
If the greenhouse soil does not meet these criteria when growing cucumbers in a greenhouse, several types of soil mixtures and systems can be successfully used. These include various types of hydroponics, peat-lith (a mixture of peat sphagnum and vermiculite or perlite) and waste from the sawmill industry (a mixture of bark, wood chips and sawdust). Hydroponic systems are capable of growing good yields of cucumbers in greenhouses, but they are more expensive and do not give particular advantages in terms of yield or quality of fruits.
Landing
For planting, pre-grown seedlings with 3-5 leaves are used, when the sprout will be approximately 26 days old. The term for planting cucumbers depends on the type of greenhouse. In greenhouses without heating, seedlings are planted in early spring, when the soil is fully warmed up. This usually happens in late April or early May. The cultivation of cucumbers in greenhouses with biological heating should be carried out from April 2 to April 8.
Landing is carried out in rows. The best distance between them on the bed is 55 cm, and between the ribbons - from 75 to 85 cm. Seedlings are planted at a distance of 22 cm from each other. Mineral or organic fertilizer is added to each well, and then water is poured. Peat pots with seedlings are lowered into the holes and filled with soil. Then the beds are well watered and the seedlings are mulched. If it was grown in containers that do not decompose, then it is removed from them and planted in a hole.
Winter landing
Despite the fact that the cucumber is hard to tolerate frosts, it is possible to grow cucumbers in the greenhouse in winter. In this case, they are usually cultivated in two turns. The first turn involves planting seedlings from January to March (depending on the type of cucumber), and harvesting takes place in July. The second rotation of the planting is carried out in early August, and the crop is harvested in the fall - in September-October. Nevertheless, it should be noted the inappropriateness of growing cucumbers in a greenhouse in winter due to the high material costs of maintaining the required temperature.
Bag method
A very convenient way is to grow cucumbers in a greenhouse from seeds, and not from seedlings. Not only ordinary people, but also professional agronomists choose this method. With this method of planting, ordinary plastic bags of 70 liters are used, which are filled with nutrient medium for future plants. Bags must first be punched with drainage holes. Composted and leached material is preferable to fresh, because when it is watered, it begins to rot and emit carbon dioxide, which is necessary for cucumbers.
You can also use the following plant debris: mixtures of branches, roots, bark, sawdust, etc. Turf or leafy soil is laid on top. From one to three seeds or one seedling are planted in one bag. It is noteworthy that you can use this method not only in the greenhouse!
Fertilizers
Cucumbers in a greenhouse grow rapidly, so they should never suffer from a lack of water or nutrients. The care and cultivation of cucumbers in a greenhouse involves fertilizing. The level of nutrient intake in greenhouse cucumbers is very high. One study shows that 8,000 plants may require 11 kg of nitrogen, 2 kg of phosphorus, and 16 kg of potassium per week during peak ripening. Therefore, fertilizer application should be systematized to achieve good yields.
Animal manure, used as fertilizer, can supply some of the necessary nutrients. However, only about a third of the nitrogen and phosphorus in them become available to plants during the growing season. Excessive use of such fertilizer will increase soil salinization and slow down the growth of cucumbers. For soils that are acidified due to the use of fertilizers or natural soil conditions, limestone may be required, which will need to be introduced before planting.
Important element
When growing crops, nitrogen is the most important element. It does not matter whether the cucumber is grown in winter greenhouses or in the summer, it must be supplied to the irrigation water with each spraying, from soluble fertilizers - potassium, calcium or ammonium nitrate. The most effective method of supplying water and nitrogen to soil layers or sandy culture is through a drip or jet irrigation system.
The nutrient solution is used in the method of planting in a bag through spraying or through a drip irrigation tube. The frequency of use will depend on the size of the plant and the temperature of the greenhouse, but will vary from one or two times a day immediately after transplantation to several times a day on warm days during harvesting.
Harvesting and Storage
You need to collect the fruits after they have reached the same diameter along the entire length, but before yellowing on the plants. Cucumber yield depends mainly on the length of the harvesting period, as well as on the distance between plants, pruning, available light, prevailing temperature, variety and good nutrition. Timely pest control also affects it. But it’s worthwhile to clarify that a cucumber grown in a greenhouse in winter in compliance with the requirements for all these items will not differ from its summer relatives!
After harvesting, a thin-skinned fruit is very susceptible to softening due to moisture loss. As soon as possible after harvesting, cucumbers should be placed in conditions that extend their shelf life. The best temperature is 12 degrees, with a relative humidity of 80 to 90 percent. Storage at lower temperatures leads to a deterioration in taste and a decrease in their lifespan.
Disease
Agricultural technology for growing cucumbers in a greenhouse will be useless if you do not identify the pest in time and begin to fight it! Aphids (an insect causing disease) appear from other susceptible crops and weeds outside the greenhouse. Whenever possible, it is important to set greenhouses away from susceptible field crops and to support controlled weed growth.
Powdery mildew (powdery mildew) can seriously affect plant growth and the quality of cucumbers. Resistant cucumber varieties are available for growing in a greenhouse and should be used where this disease is a problem. Control measures should be applied when the first mold spots are noticed. Powdery mildew looks like small white dusty spots of small diameter. Usually they appear first on the upper side of the lower leaves.
Gray mold occurs when the humidity when growing cucumbers in a polycarbonate greenhouse is not properly controlled. Fortunately, this disease can be completely prevented by ensuring adequate air circulation in the room in time.
Fungal damage can also be a serious problem for young cucumbers. Symptoms are softening and yellowing of stem tissues on the soil line, and then their withering. Young plants are very susceptible for several days after transplanting, but the disease can also slow growth if the infection appears on ripening fruits. Good sanitation methods and sterilization of the growing environment before planting will prevent this ailment.
Fruit curvature
A serious physiological disorder, which leads to a decrease in the yield and quality of greenhouse cucumbers. The curvature of the fruit is already noticeable at an early stage of ripening and cannot be corrected.
It is known that the thrips insect, feeding on one side of the young fetus, leads to the curvature of the cucumber. Growing in a greenhouse in winter can be accompanied by an unfavorable temperature, excessive soil moisture and poor nutrition. These factors also deform the fruits.
Insects
The list of the main pests of greenhouse cucumbers includes a white fly, a diptera mite, plant leafworms, and greenhouse thrips.
The greenhouse environment is attractive to these pests, so gardeners must constantly monitor the development of their populations. Insects climb into the greenhouse through ventilation openings, open doors, even through small openings in the walls or roof. They can also be fixed on clothing or tools. Regular inspections of plants for lesions will guarantee the appearance of healthy cucumbers in the greenhouse. Growing using the recommendations of this article will bring a rich harvest and the opportunity to try yourself in a new business!