Alexander Yurievich Shagaev, agronomist consultant with 15 years of experience working at greenhouses to share information on the influence of nutrient solution concentration on the development of protected crops.
Low concentration of nutrient solution causes vegetative growth, respectively, in the summer, when strong solar activity, all plants are hung fruit. If the concentration is reduced, the plant will continue to grow vigorously. It is also possible to determine whether there is concentration in the color of flowers, or it is clearly visible on cucumber and tomatoes. If the flower is pale yellow, then the concentration is lacking and the experienced colored agronomist can determine if the concentration is to be added or not. Pale flowers do not like bumblebees and they can work badly on them, and they strike bright colors, right up to the fact that the pollen pipes get caught.
If the concentration of nutrients is low, the water does not stop. We can only reduce or increase the concentration in the dropper. If there is not enough water in the mat, you need to increase drainage, for example, do long irrigation. At night, when the evaporation is not large, do short watering, then water is kept in the mat, also seal the drainage hole, and then the passage of water rises quickly.
The Dutch do not do the separation of the contents of the nutrition elements. They count the primary solution, make it in the tanks A and B. In the rest of the stages, they control the concentration of nutrient solution (EC). Solutions are needed on the initial calculation, and everything else is controlled by the concentration of nutrient solution. You want to shift the plant to the generative side, so that it gives more fruits and fewer leaves, increases the concentration, want to grow vegetatively, lower the concentration. Therefore, there are two directions - more, or less water consumes the plant. Here the ratio of nutrients is never taken into account anywhere.
When Olga Anatolievna taught us agrochemistry, she said that there are solutions for different periods of life, which we change once a week or every two weeks. They exist, but today Olga Anatolievna works all year round on one nutrient solution. When I asked her the question: "Remember, you were taught 10 years ago that there are many solutions?" She said that it was 10 years ago, and now it has changed and equipment has changed. She believes that only by changing the concentration of nutrient solution and the percentage of drainage, we are leaving the replacement of nutrient solution. We take one nutrient solution and begin to work from seedlings and before liquidation. And such a technique brought Olga Anatolievne a yield of 93 kg / m2 of tomatoes. This is the highest result for today, this year, a bit less, but as she said: "This is due to the fact that we have made interplanting, not destroyed, but now we are forced to leave the interplanting and clean the entire plant." Let's see what they will be next year. The task she put in front of her team - 100 kg / m2 of tomatoes, and, I think, it is their strength. First, because the combine is in a good zone, and secondly, it is a combine of the Ultra Klima type, that is, it can withstand constant humidity and temperature. The fifth-generation manufacturing unit is 40 times more expensive than usual and operating costs are higher, but for the turnover from August to July this year they received 8500 rubles / m2. This despite the fact that 5-6 thousand Rubles are considered not to be a bad result. Therefore, they build, and will continue to build more greenhouses.
You should never water the plant with water. Once drained only with water - destroyed all crop, so if there is no fertilizer, it is better to throw out the crop than to water it with water. If you drink water in one day, then you cannot get fertilizer next day, or get cracking of the stem, fruits and everything else. It is very difficult to restore balance. As a result of violation of osmotic pressure in plants, there is a breakdown of cell walls. A disturbance of osmosis causes an endemic that breaks the plant from the inside out. Endemic is the movement of water towards the greatest concentration of salts, which leads to a rupture of stems and damage to the roots. Such damage will not be restored, as it is internal damage, which in the future are the focal points for the development of infections. You do not see the damage at the moment on the plant, but it is already doomed.
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