What should be paid attention to when applying base fertilizer to vegetables in greenhouse

Greenhouse vegetables have high multiple cropping index, high yield and large fertilizer requirement, while the base fertilizer has a great influence on the yield, quality and soil properties of vegetables, which is the most basic link in fertilization and is very important to the growth and development of vegetable crops. Therefore, the base fertilizer must be applied reasonably, and the following problems should be paid attention to when applying the base fertilizer:

1. Determine the amount of fertilizer application according to the target yield of vegetables

In order to determine the amount of bottom fertilizer applied in greenhouse, we must consider the level of soil fertility and the amount of fertilizer required by vegetables. In general, 30% of the total amount of nitrogen fertilizer, 80% of phosphate fertilizer, 50% of potash fertilizer as base fertilizer, biological fertilizer and micro-fertilizer as far as possible all at one time. For example, the yield of autumn tomato is about 8000kg to 9000kg. For every 1000 kg tomato produced in this range, it needs to absorb 4.4kg of nitrogen, 1.1kg of phosphorus pentoxide, 4.8kg of potassium oxide, and the ratio of nitrogen, phosphorus and potassium is 1 ∶ 0.25kg ∶ 1.1, and more calcium and boron are needed. Among them, high phosphorus type fertilizer should be selected for base fertilizer and low phosphorus type fertilizer should be selected for topdressing. The suitable amount of base fertilizer is 40-50 kg, the proportion of nitrogen, phosphorus and potassium is 1 ∶ 1 ∶ 0.75, the amount of topdressing is 75-85 kg, and the ratio of nitrogen, phosphorus and potassium is 1 ∶ 0.2 ∶ 0.85.

Second, ensure that the amount of organic fertilizer is adequate

Organic fertilizer (including farm manure, barnyard manure and cake manure) is the most suitable to be used as base fertilizer, and more bio-organic fertilizer should be applied to the aged greenhouse with high soil fertility. In order to keep the soil fertility and organic matter in the greenhouse not decreased or slightly increased, it is necessary to supplement organic fertilizer to the greenhouse soil. According to the change law of soil organic matter in greenhouse and the principle of the highest yield when the ratio of organic nitrogen to inorganic nitrogen is 1 ∶ 0.4: 1, in order to keep the soil organic matter in greenhouse above 2% to ensure higher yield, organic fertilizer with 30% organic matter content should be applied not less than 2000 kg / mu every year.

3. Determine the application method of base fertilizer according to the weather and growth characteristics.

When applying base fertilizer, we should mainly use large volume of crude organic fertilizer such as rotten soil miscellaneous fertilizer and manure, with a dosage of 60.8 cubic meters per mu to increase soil organic matter and carbon matter. at the same time, it should be combined with a small amount of high-quality bio-organic fertilizer (100kg-150kg) and slow-release potassium sulfate compound fertilizer 75kg-100kg. Controlled release fertilizer was used to regulate the release rate of nitrogen fertilizer in base fertilizer to avoid high temperature and root diseases. After fruit setting, all-element fertilizers containing nitrogen, phosphorus and potassium should be applied with water.

Li Chunzhen, Agricultural Bureau of Gucheng County