Is urea or compound fertilizer better for topdressing lettuce? What are the techniques for topdressing lettuce?

Lettuce is a plant that likes cool climates. Although suitable varieties are selected for planting according to different climate conditions throughout the year, lettuce itself does not like high temperatures. In hot weather, it will cause the lettuce to bolt early, resulting in low yields. So, is urea or compound fertilizer better for topdressing lettuce? Let's take a look at the introduction provided in this article!

Is urea or compound fertilizer better for topdressing lettuce?

The topdressing of lettuce should be mainly nitrogen fertilizer, supplemented by potassium fertilizer. At the same time, you can also use an appropriate amount of photosynthetic nutrient film fertilizer, which can make the lettuce absorb light energy better in the future and enhance photosynthesis. If the soil of the lettuce field is severely acidic, lime can also be used for topdressing. Lime can adjust the acidity of the soil and make the lettuce grow more vigorously.

What are the techniques for topdressing lettuce?

Topdressing of spring lettuce, 3 times in total

Spring lettuce is usually sown after September. The first topdressing is arranged after planting, with 15 kilograms of urea or about 1,000 kilograms of human feces and urine applied per mu, in order to promote the survival rate of transplanted seedlings. The second topdressing is arranged when the lettuce turns green the following year, with 20 kilograms of urea applied per mu, combined with watering. The third topdressing is during the expansion period of the lettuce stems, when the fertilizer requirement is very large. You can apply 20 kilograms of urea and 20 kilograms of potassium dihydrogen phosphate. After that, there is no need for topdressing, just wait for the harvest.

Autumn lettuce topdressing also needs 3 times

Autumn lettuce is usually sown after June, and the growing period lasts up to 3 months. During these three months, topdressing is required 3 times in total. The first time is arranged after planting, and 20 kilograms of ammonium sulfate are applied per mu. The second time of topdressing is arranged when the plants are "grouped", and 20 kilograms of urea are applied in combination with watering. The third time of topdressing is also placed during the period of stem expansion. In addition to applying 20 kilograms of urea per mu, 100 kilograms of potassium dihydrogen phosphate solution are also required to be sprayed on the leaves.

From the above analysis, we can know that whether it is autumn lettuce or spring lettuce, the time of topdressing is arranged according to its growth law. The fertilizer used is mainly urea, and the application amount per mu is basically the same.

What should I pay attention to when fertilizing lettuce?

1. Leaf lettuce: If the lettuce is eaten for its leaves, then more basal fertilizer can be used, such as a mixture of organic fertilizer and compound fertilizer. The amount of topdressing for leaf lettuce should be controlled. More topdressing can be used after planting, and less topdressing should be used in the later period. Nitrogen fertilizer cannot be used in the 20 days before harvest. If too much nitrogen fertilizer is used, the leaves will be too old and the taste will be greatly reduced.

2. Lettuce for stems: There is a kind of lettuce whose leaves are not only edible but also its stems. When applying base fertilizer, more calcium fertilizer should be applied. When the lettuce leaves grow out, top dressing should be applied. When the stems grow rapidly, more top dressing should be applied.

There is a difference in fertilizing leaf lettuce and stem lettuce, so you must understand the characteristics of these two types before planting and apply fertilizer according to their characteristics. In this way, the yield and taste of the lettuce grown will be better.