When to Fertilize Watermelons? Detailed Guide to Timing and Methods

Fertilizer requirements of watermelon and high-yield fertilization techniques and timing: Watermelon has lush stems and leaves, grows quickly, produces large fruit and high yields, requires a lot of fertilizer, and demands comprehensive soil nutrients. If nutrients are insufficient or the nutrient ratio is improper, it will seriously affect yield and quality.

1. Fertilizer formula: Applying nitrogen, phosphorus and potassium in a suitable ratio can significantly improve watermelon quality. Based on this principle, various regions have developed watermelon-specific fertilizers formulated with nitrogen, phosphorus, potassium and micronutrient fertilizers according to soil fertility conditions and the nutrient uptake characteristics of watermelon. Suitable watermelon-specific controlled-release fertilizer ratios (nitrogen-phosphorus-potassium) mainly include 18-14-18, 15-14-21, etc. Some of the above watermelon-specific controlled-release fertilizers have added the medium and trace elements needed for watermelon production.

2. Fertilization timing and method: Apply once as a base fertilizer before sowing watermelon, or determine the fertilization period and interval based on the release period of the controlled-release fertilizer. Apply the controlled-release fertilizer as a base fertilizer once in a furrow; when transplanting watermelon seedlings, keep a distance of about 10 cm from the furrow-applied fertilizer.

3. Fertilization amount: About 80 kg per mu, adjusted appropriately according to the target yield.

4. Precautions: Watermelon should not be given chlorine-containing fertilizers, because watermelon is a chlorine-sensitive crop, and applying chlorine-containing fertilizers will affect watermelon quality. The fertilization site must not be too close to the watermelon seedling roots, to prevent root damage and seedling burn.

5. Fertilization effect: Lush stems and leaves, green leaves, and sturdy vines; increased fruit weight and higher yield; overall sweetness of the fruit is more uniform, nitrate content is reduced, and quality is significantly improved.