Methods of Soilless Vertical Cultivation in Vegetable Greenhouses

1. Construction of Cultivation Troughs: Laying a Solid Foundation for Crop Growth

Taking cherry tomatoes as an example, the cultivation troughs adopt the method of "excavated trenches + plastic film laying", with specific steps as follows:

1. Trench Excavation: Adopt a wide-narrow row planting mode, with the row spacing controlled at 60-70cm. Dig triangular cultivation troughs in a single row. The trough mouth is 20cm wide and 25cm deep. It is necessary to ensure that the bottom of the trough is flat to avoid root rot caused by local water accumulation;

1. Leakage Prevention Treatment: Lay plastic film in the trenches to isolate soil impurities and prevent water leakage;

1. Substrate Filling and Transplanting: Fill the plastic film with fermented and decomposed straw as the cultivation substrate. After filling, tamp it down with feet to ensure the compactness of the substrate; then transplant cherry tomato seedlings, keeping the plant spacing at 35cm to ensure sufficient growth space for the plants.

2. Installation of Drip Irrigation Equipment: The Key to Precise Water and Fertilizer Supply

The drip irrigation system is the core equipment for delivering inorganic nutrients and water in soilless cultivation, which directly affects the crop growth efficiency and requires scientific configuration and laying:

1. Composition of Core Equipment

· Power Equipment: Choose according to regional conditions. In areas with shallow groundwater levels, drill a plastic hose well in a single greenhouse and match it with a self-priming pump to meet the needs; water towers and centralized water supply frequency conversion water pumps can also be used;

· Auxiliary Equipment: Including specially designed fertilizer tanks (reducing water pressure loss and preventing fertilizer from clogging filters), filters, water meters, as well as polyethylene branch pipes with a diameter of 32-40mm, and capillary tubes with a dripper spacing of 20cm (a small dripper spacing can increase the number of substrate wetting points, which is beneficial for root absorption).

2. Key Points for Pipeline Laying

· The branch pipes should be parallel to the back wall of the greenhouse. It is recommended to disconnect them in the middle and connect them to the fertilizer tank through a tee to make the water flow diverge from the middle to both ends, ensuring uniform water and fertilizer delivery;

· Lay one capillary tube per row of cultivation troughs. The capillary tube should be placed in the middle of the trough, with the dripper facing upward to reduce the probability of clogging.

3. Nutrient Solution Management: Supply on Demand to Improve Water and Fertilizer Utilization

Different from the traditional nutrient solution method of "mixing and dissolving macro, medium and micro elements", this technology adopts the method of adding in groups and directly dripping into the substrate, which can effectively avoid the chemical precipitation problem caused by the alkaline groundwater in northern China. The specific management plan is as follows:

1. Method of Adding Nutrient Solution

Store fertilizers that are prone to precipitation separately. During drip irrigation, first add one group of fertilizers into the fertilizer tank. After they are completely dissolved with drip irrigation and penetrate into the substrate, pause the drip irrigation, then add another group of fertilizers until the drip irrigation is completed.

2. Water and Fertilizer Regulation in Different Growth Stages

· Early Transplanting Stage (within 10 days): The plant roots are shallow, and drip irrigation of nutrient solution is easy to cause waste, so manual fertilization is used instead. Dissolve nitrogen, phosphorus and potassium fertilizers in a bucket at a concentration of 1g/L, and water around the seedlings once a day;

· Early Drip Irrigation Stage (when seedlings are small): The water and fertilizer consumption is low, with 0.5 cubic meters of water and fertilizer dripped every day, divided into two times in the morning and afternoon, adding one group of fertilizers each time;

· Autumn and Winter Seasons: Adjust according to the seedling condition and weather. Generally, the daily irrigation volume is controlled at about 1 cubic meter. Drip irrigation is carried out in the morning on sunny days, and no irrigation on cloudy days; the amount of irrigation can be flexibly adjusted by observing the accumulation of nutrient solution in the cultivation troughs;

· Spring Season: The temperature rises and the light is sufficient, so cherry tomatoes grow rapidly. The daily amount of drip irrigation water and fertilizer is controlled at about 1.5-2 cubic meters.

4. Cultivation Effects: Dual Improvement in Quality and Benefits

Compared with traditional soil cultivation, cherry tomatoes grown by soilless vertical cultivation have better performance in many aspects:

1. Better Quality: The sugar content is increased by 26.3%, with pure taste, sweet and sour taste, and better texture;

1. Greener and Safer: The amount of pesticides used is only 1/4 of that in soil cultivation, reducing the risk of pesticide residues;

1. Water and Fertilizer Saving: Each greenhouse uses 150 cubic meters of water, and the fertilizer purchase cost is 1,500 yuan per greenhouse, which is about 350 yuan per greenhouse less than that in soil cultivation;

1. Higher Benefits: The yield is basically the same, but the overall benefit is increased by more than 20%, with significant economic and ecological benefits.