Tomatoes often lack phosphorus and potassium because of improper fertilization time. What should I do at this time?

Tomatoes planted in the open field or protected field have low yield, poor quality and poor profitability due to insufficient fertilization time and weak growth potential. Therefore, in the whole growth period of tomato, the best fertilization period for Xihong should be determined according to its growth characteristics. Learn to apply fertilizer scientifically and accurately to ensure high quality and high yield of tomatoes. In winter, the long-term closure of the shed and improper management often lead to the violation of discipline and affect the normal growth of tomatoes. The gas loss of greenhouse tomatoes in winter is mainly caused by improper autumn rain. According to the weather forecast before spraying water, it will clear up at least 3~5 days after watering. In addition, if the rainy day suddenly clears up, plants may have many wilting symptoms, so you can't rush to water and fertilize. Otherwise, root suffocation will lead to physiological withering and even death of plants.

Nutritional types should be determined according to the growth of tomatoes. Results In the early stage, the plants were vigorous and easy to grow, so foliar nutrition to promote the growth of stems and leaves should be used less, and potassium dihydrogen phosphate and S inducer could be used. Therefore, as the growth momentum of plants begins to weaken, foliar nutrition for promoting the growth of stems and leaves should be used to promote the growth of seedlings, and various foliar special nutrient solutions such as Shifeng 48 1, amino oligosaccharide and lentinan can be selected. The type of nutrition depends on the weather. Plum rain weather, insufficient sunlight in greenhouse, insufficient photosynthesis, insufficient sugar supply in tomato, and good foliar spraying effect. Timely foliar calcium supplementation. Tomato fruit needs more calcium for growth. When the soil lacks calcium, the fruit is prone to navel rot. Therefore, it is recommended to spray simple active calcium, calcium superphosphate, calcium amino acid, calcium drill and other calcium fertilizers at the fruit-bearing stage of tomatoes to meet the calcium demand of tomatoes.

The interval of foliar fertilizer should be appropriate. The suitable interval of foliar fertilization for tomato is 5~7 days. Among them, the interval between inorganic fertilizers that are easy to spray on leaves is longer, generally not more than 7 days. The spraying interval of organic nutrition can be appropriately short, generally about 5 days. Combined with epidemic prevention measures, get twice the result with half the effort: foliar fertilizer in greenhouse in winter and spring will often greatly increase the air humidity in protected areas, which is easy to cause leaf spot diseases such as gray mold, leaf mold and morning and evening diseases. Therefore, it is necessary to reduce the frequency of foliar spraying fertilizer on cloudy days.

Tomato has a long growth cycle and strong ability to bear fruit continuously. It needs a lot of nutrient supply during the whole growth period, but the absorption of nutrients by tomatoes at different growth stages is different. For example, in the early stage of tomato growth, due to the low absorption of nitrogen and potassium fertilizer, the reproductive organs increased. Therefore, to ensure high yield in tomato planting, we should not only apply base fertilizer, but also harvest fertilizers with different nutrients in time according to the growth and development law of plants.