How to Fertilize Lettuce? Master the Key Points of Fertilization Timing and Methods

Lettuce is a common vegetable in our daily lives. Its stems can be stir-fried or served cold, with a crisp taste and rich nutrition, and its leaves are also edible; it is also called shengcai (leaf lettuce). To grow lettuce well, the key point is fertilization, so how should lettuce be fertilized? Let's take a look.

1. Nutrient Requirements

Lettuce needs more than a dozen elements during growth, among which the three most conventional are nitrogen, phosphorus and potassium. It has the greatest demand for potassium. According to research, for every 1000 kg of lettuce produced, 4.5 kg of potassium fertilizer is consumed. During the seedling stage, its fertilizer requirements are not high, and as it gradually grows, its demand for fertilizer becomes greater and greater. The head-forming stage of lettuce is the period of greatest fertilizer demand, and during this period the demand for nitrogen fertilizer accounts for more than 80% of the entire growth period.

2. Fertilization Principles

Lettuce needs relatively many elements, so in order to avoid deficiency symptoms, organic fertilizer should be applied more to provide what it needs for growth. At the same time, nitrogen fertilizer should be controlled to avoid excessive application, which would affect the root system's absorption of other elements, and potassium fertilizer should also be applied more. Fertilization should mainly use base fertilizer, with appropriate topdressing. Topdressing should mainly use nitrogen fertilizer, reasonably combined with phosphorus and potassium fertilizers. When fertilizing, combine it with water management, which can improve fertilizer use efficiency, speed up absorption by the root system, and promote growth.

3. Fertilization Recommendations

For base fertilizer, generally 1000-1500 kg of decomposed farmyard manure is applied per mu, and later topdressing should be carried out according to the yield per mu. For fields with a yield per mu of more than 3500 kg, apply 10-12 kg of nitrogen fertilizer, 4-6 kg of phosphorus fertilizer, and 10-14 kg of potassium fertilizer per mu as topdressing; for a yield per mu of 2500-3500 kg, apply 6-10 kg of nitrogen fertilizer, 3-4 kg of phosphorus fertilizer, and 8-10 kg of potassium fertilizer per mu as topdressing. According to this ratio, as the yield per mu decreases, gradually reduce the application amounts of nitrogen, phosphorus and potassium fertilizers.

4. Precautions

When fertilizing, note that lettuce has poor acid tolerance, so when fertilizing, use acidic fertilizers as little as possible. When the soil pH value is below 6, apply 150-200 kg of quicklime per mu to adjust it. Nitrogen fertilizer should all be applied as topdressing, generally divided into three stages; potassium fertilizer is generally used as base fertilizer, with the rest applied in two portions; phosphorus fertilizer is all used as base fertilizer.

The above is an introduction to how to fertilize lettuce. I hope it can help you. If you want to learn more related knowledge, please stay tuned to us.