Lotus roots are heavy feeders and have strict requirements for soil conditions. Lotus fields require clay soil rich in organic matter, with a pH level ranging from 6.0 to 7.5 and containing various trace elements. However, relying solely on soil nutrients is not sufficient; timely fertilization during the growing season is essential. So, what are the key points and considerations for fertilizing lotus roots? Let's find out.
Key Points for Fertilizing Lotus Roots
1. Fertilization Requirements
Lotus roots, which are consumed as swollen underground stems, require significant amounts of nutrients. Under normal conditions, with a yield of 2000-2500 kilograms of fresh lotus roots per acre, the absorption of pure nutrients by lotus roots is approximately 9.9 kilograms of nitrogen (N), 4.0 kilograms of phosphorus pentoxide (P2O5), and 15.2 kilograms of potassium oxide (K2O). The absorption ratio of nitrogen, phosphorus, and potassium by lotus roots is roughly 1:0.38:1.5. Therefore, it is recommended to use high-concentration potassium sulfate compound fertilizer in production.
2. Fertilization Methods
(1) Base Fertilization:
Base fertilization is usually applied during land preparation. For every acre, apply 2500-3000 kilograms of livestock manure, 25 kilograms of ammonium bicarbonate, 10-15 kilograms of potassium sulfate, 50-100 kilograms of hydrated lime, 50 kilograms of calcium superphosphate, and 150 kilograms of cake fertilizer. Then, plow to a depth of 20-30 centimeters and level the soil.
(2) Topdressing:
Throughout the growth period, lotus roots generally require topdressing 2-3 times:
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The first topdressing should be done when 3-5 leaves appear in the field. Apply 25-30 kilograms of nitrogen-phosphorus compound fertilizer per acre.
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The second topdressing should occur when lotus roots have 6-7 leaves and are in vigorous growth. Apply 1000-1500 kilograms of decomposed manure and 25 kilograms of compound fertilizer containing nitrogen, phosphorus, and potassium per acre.
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The final topdressing should be done when the roots start forming. Apply 1500-2000 kilograms of manure and 15-20 kilograms of ammonium dihydrogen phosphate per acre.
Considerations for Fertilizing Lotus Roots
1. Weather Conditions
Choose clear, windless weather for fertilizing lotus roots to avoid application during the intense midday sun.
2. Water Management
Before fertilizing, drain the field, then apply fertilizer, and finally, irrigate to the original depth.
3. Dosage
The amount of lotus root fertilizer applied depends on the fertility of the soil. It is advisable to apply thin and frequent fertilization to prevent leaf burn and waste of fertilizer.
4. Depth of Application
The fertilization method varies between shallow and deep water lotus fields. For shallow water fields, both compound fertilizer and single-component fertilizer can be applied. However, in deep water fields, it is best to mix compound fertilizer with mud to prevent fertilizer floating.
5. Proper Use of Growth Regulators
When topdressing, using plant growth regulators such as gibberellins can enhance plant growth, increase nutrient absorption, and promote higher yields.
In summary, mastering the fertilization techniques for lotus roots involves paying attention to key fertilization periods and adopting appropriate methods. By doing so, you can achieve optimal fertilization and high yields.
