Currently, there are many technologies, but the most widespread in Russia is the flow culture. It is as follows: plants are grown in pots with a diameter and height of 5 cm. When growing seedlings, pots are placed in foam cassettes of 54 pieces. Filling them with soil, sowing and watering is carried out automatically. After watering, the cassettes are placed in a germination chamber with an air temperature of 22°C and a relative humidity of 90% and kept there until the seeds germinate (lettuce 3 days, dill 4 days and parsley 7-8 days). Then they are placed in a seedling section with an air temperature of 18-20 ° C, round-the-clock additional illumination with an intensity of 7000 lx / m2 and automatic watering. The growing period in the seedling section of lettuce is 12 days, dill 11 days and parsley 18 days. Next, the pots are placed in the gutters in a checkerboard pattern of 31-32 pots. The gutters are on the conveyor and the first part of the cycle moves closely, and at the final stage they are placed at 18-20 cm. with an intensity of 3500 lx/m2. The growing period for lettuce is 17 days, dill 16 days and parsley 19 days.
The use of flow technology is very tempting, it is necessary to take into account only a few subtleties. When completing equipment for the preparation and supply of a nutrient solution, the main attention should be paid to the reliability and non-failure operation of the solution supply system (primarily the pump) and the accuracy of dosing components. The most effective use of automatic mixers-dispensers with computer control. They allow you to constantly monitor and adjust the composition of the solution, excluding overdose. The use of manual injector dispensers is simpler and cheaper, but it does not provide sufficient accuracy in dosing the components of the solution, there may be cases of overdose due to errors of the attendants.
The nutrient solution in the lettuce line circulates in a closed loop. When flowing through the gutters, it becomes contaminated, soil particles, plant residues and root secretions enter it. Therefore, when completing the equipment, it is necessary to pay attention to the circulating solution filtration system, which should include gravel (sand) and disc filters.
With repeated use, plant pathogens and algae get into it and multiply. This can create very big problems, in order to avoid this, it is necessary to equip the salad line with a recycle solution disinfection system. In addition, this will allow for less frequent complete replacement of the nutrient solution, which results in tangible savings in fertilizer and labor costs.
In the future, for successful work on the lettuce line, the following parameters must be observed: the equipment must be carefully installed, especially with regard to the slopes of the gutters, from the very beginning of operation it is necessary to monitor the state of the gutters, constantly clean and disinfect them, monitor the efficiency of the filtration and disinfection systems circulating solution, use seeds and peat free from pathogens, observe quarantine and maintain agrotechnical parameters (especially with regard to temperature).емпературного режима).