Fertilization management technology of lettuce

1. Characteristics of fertilizer requirements

Lettuce likes to grow in a warm environment, has very poor cold resistance, and has a relatively large demand for water and nutrients. The main edible parts of lettuce are underground tubers, so the requirements for soil are relatively high. When planting, ensure that the soil is strong and deep and soft. The nutrient requirements of lettuce during the growth process will vary depending on the growth stage. In the prosperous period, the amount of fertilizer required is very large, so pay attention to fertilizing in time, and then appropriately reduce the amount of fertilizer in the mature period to prevent the decline of storage capacity. The potassium requirement of lettuce is larger, followed by nitrogen, and then phosphorus.

2. Apply enough basal fertilizer

The root distribution of lettuce is relatively shallow, and its depth is about 25 cm. Therefore, the application of base fertilizer is very important, and the application of sufficient base fertilizer is the key to ensure the healthy growth of lettuce. It is also an indispensable work for cultivating high-quality strong seedlings. We need to control the amount of fertilizer according to the planting area. Generally, about 4500kg of base fertilizer is applied per mu. The base fertilizer is mainly decomposed farmyard manure, with an appropriate amount of superphosphate, plant ash and other substances. Promote the growth of lettuce and meet the nutritional needs of the growth of lettuce.

3. Reasonable top dressing

When planting lettuce, we should carry out reasonable top dressing according to the season. The planting time of spring lettuce is generally around September of the first year, and then it will enter a dormant period and stop growing in winter. When topdressing spring lettuce, we should adhere to the principle of adding more and less. After planting, the first top dressing can be carried out to improve the survival rate of planting. Then, about half a month after the planting, top dressing again, and the top dressing fertilizer can also be mainly farmyard manure. However, if the soil fertility is large and the base fertilizer is sufficient, the amount of top dressing can be reduced or even no top dressing is required.

4. Topdressing during rosette period

It is very important to fertilize lettuce in the rosette stage and the succulent stage. The nutrition at this time directly affects the yield. When the head of lettuce is about 4 months, the demand for nitrogen will increase sharply. Therefore, it is necessary to pay attention to appropriately increasing nitrogen elements, and then pay attention to supplementing the appropriate amount of calcium, iron and other nutrients. Promote the growth of leaves, enhance photosynthetic capacity, and increase the accumulation of photosynthetic substances in lettuce. Then according to the actual situation such as the growth stage of the lettuce, the nutrition is reasonably supplemented, and top dressing is carried out to meet the nutrition required for the rosette and expansion of the lettuce.