Cucumbers in greenhouses shall grow in soil, enriched with peat substrate or in formed beds with peat substrate as well as in cylinders and containers filled with peat substrate. Universal peat substrate, suitable for various vegetables and flowers as well as for improvement of the soil that are made under the special recipe of ecological, clean, mid-fraction peats with required quantity of micro and macro elements (pH – 5,5-6,5; EC- 1,6-1,9 mS/cm), enriched with additives shall be used. Also universal peat substrate, suitable for vegetables and made under the special recipe of ecological, clean, mid-fraction peats with required quantity of micro and macro elements (pH – 5,8-6,2; EC- 1,7-2,2mS/cm) can be used. Substrate shall be aired and additionally watered prior to the seedlings planting.
Cucumber seedlings planted into the greenhouse shall be of 25-30 cm height and have 5-6 leaves as well as good roots. The density of plants planting shall be 2,5-2,8 plant/m2, leaving the passage paths. Optimal temperature at roots area shall be 18-20 oC. In case the soil cannot be heated even till 16 oC, it is recommended not to plant the cucumbers at all and wait until the weather gets warmer. Seedlings shall be planted deeper than they have grown in the nursery.
Cultivating the cucumbers in soil, enriched with peat substrate or made only of peat substrate, the plants get infected with diseases and pests over the few years. Thus the old soils shall be replaced by the new one.
It is more economical to grow the vegetable in plastic packages (cylinders) or in containers (plastic bags) filled with peat substrate, thus using less peat substrate than growing the plants in soil. Every year plants are planted into a new peat substrate, giving them better conditions, thus the plants grow significantly healthier.
After 4-5 days plants shall be tied to the wires, stretched at 1,8-2 m height. In order to form a valuable plant with a good roots, all offsprings, blossoms and fruits at their early stage must be picked up from the main stem up till 60 cm height. After the plants grow over the upper wire, 2-3 offsprings shall be directed downwards (formation of “umbrella”).
Cucumbers like heat and do not like sudden change of temperatures. The most favorable temperature for cucumber growing is 22-28 oC at day time and 18-20 oC at nigh time, maintaining the relative air humidity of 80-90 proc. In summer time, when the air gets very warm inside the greenhouse, the passage paths and beds are watered without pouring water onto the plants.
Cucumbers shall be watered seldom, but abundantly prior to their blossoming. In this case they grow less, but form more blossoms. Blossoming and started fruiting plants shall be watered more often, but less. Fruiting cucumbers shall be abundantly watered with warm (22-25 oC) water, in the first half of the day, without pouring the water onto the leaves.
After planting, cucumber seedlings are recommended to be watered with 0,2 proc. Ruter AA solution. Ruter AA increases the plant resistance to stress and promotes roots formation. Cucumbers grow very quickly and give very good harvest within a relatively short time, so they need a lot of nutrients. Cucumbers plants, until the fruits start shall be fertilized with 0,2 proc Nutricomplex (14-11-25) and 0,1 proc. calcium nitrate solution and while fruiting – with Nutricomplex (6-10-32 or 6-14-30) and 0,1 proc. calcium nitrate solution. In case of cloudy and non-sunny days, the cucumbers are recommended to be fertilized with 0,2 Boramin calcium solution, which promotes the blossoms formation. EC in solution (salt concentration on the solution) shall not contain more than 2,5. Acidity of the watering water shall be adjusted with the Sray Plus solution. In case there is a high temperature and low humidity in the greenhouse, the cucumbers are infested by spider-mites and thrips. Plants shall be sprayed with vertimec 0,3 proc. and nimazal 0,5 proc. solution. When the humidity is increased and temperatures are changing, the cucumbers get yellowish and infected with downy mildew. It is recommended to spray preventively with pervicur 0,25 proc.
During the growing, it is necessary to grant the control of excessive concentration of salts in peat substrate, not to over-fertilize with nitrogen fertilizers. It is necessary to remove the infected and already endangered plants.