During the growth of tomatoes, they are very sensitive to top dressing in various critical periods. Therefore, reasonable top dressing has a great influence on tomato yield. So how to fertilize tomatoes? What should be paid attention to when top dressing tomatoes? Let's analyze it below.
Fertilization time and amount of tomato
According to the characteristics of tomato fertilizer requirements, tomato fertilization should be based on base fertilizer under the premise of cultivating strong seedlings, combined with soil preparation, applying 5-7 tons of high-quality organic fertilizer per acre, and 6-8 kg of phosphate fertilizer and 7-10 kg of potash fertilizer. The tomato should be chased once every 5-6 days after planting, and 2~3 kilograms of nitrogen fertilizer (urea) should be applied per mu.
When the tomato enters the full fruit period, when the first ear fruit is white and the second and third ear fruit rapidly swell, topdressing should be applied 2~3 times, each time 3~4 kg of nitrogen (urea) per mu, and the previous one can be used separately. With 1.5~2 kg of phosphorus and potassium, it helps to improve the quality of the fruit.
After the tomato enters the fruit, the ability of the root system to absorb fertilizer decreases. Foliar sprays such as 0.3%~0.5% urea, 0.5% potassium dihydrogen phosphate, 0.1% borax, etc. can be used to delay senescence and increase the harvest period.
For tomato fertilization under protected cultivation, it is necessary to prevent salt barriers caused by excessive fertilization. When fertilizing, the input of organic fertilizer should be increased. The amount of chemical fertilizer can be reduced by 20%~30% compared with the open field, and it should be applied in small amounts and multiple times, and pay attention to timely irrigation and pressure salt to promote the growth and development of tomatoes.
Four notes on top dressing of tomatoes:
One control: During the period from tomato planting to fruit setting, the seedlings should be topdressed and the amount of topdressing should be controlled. If the top dressing is too much and too concentrated, it is easy to cause the plants to grow excessively, and even cause the flowers and fruits to fall. Therefore, when the plants are severely lacking in fertilizer during this period, the amount of topdressing should generally be controlled, and a little dilute manure or biochemical organic fertilizer solution should be used.
Two promotion: Tomatoes should be topdressed frequently during the young fruit period and harvest period to promote their growth and development. When the first ear fruit grows to the size of a walnut, quick-acting chemical fertilizer should be applied 1-2 times quickly. Generally, 30% human manure or 5% sulfur-containing compound fertilizer extract is applied to ensure that the plants are not defertilized. After the young fruit enters the swelling period, in order to meet the needs of plant growth and avoid defertilization in the later stage, the fruit should be chased frequently to preserve the fruit fertilizer. Generally, 40% human feces or 5% sulfur compound should be applied every 10 days on a sunny day. Fertilizer extract.
Three sprays: Tomatoes not only absorb nutrients from the soil from the roots, but also absorb mineral nutrients from the leaves to promote the development of fruits and seeds. Therefore, the WeChat search vegetable farming circle is concerned. During the fruit growth period, especially when the soil cannot be top-dressed due to continuous rain in the early stage, the foliar fertilizer should be sprayed 2-3 times. The organic liquid fertilizer can be sprayed with 300-500 times liquid, and the chelated form can also be used. Multi-element compound micro-fertilizer is sprayed with 500 times liquid to improve the quality of tomatoes.
Four taboos: Topdressing tomatoes should not be carried out in the case of humid soil and high temperature at noon, and too concentrated fertilization should be avoided. Concentrated fertilization is easy to make plants grow and produce fertilizer damage; fertilization in the case of wet soil is easy to cause physiological diseases such as falling flowers, leaves and fruits; fertilization under high temperature conditions, the evaporation of plant leaves will affect the fertilizer efficiency. Tomatoes do not have strict requirements on soil conditions, but in order to obtain high yields and promote good root development, fertile loam with deep soil layer, good drainage and rich in organic matter should be selected. The pH of the soil is preferably from 6 to 7, and the soil that is too acid or too alkaline should be improved.