The Harm of Over-Fertilizing Bitter Melon and How to Deal With It

Before planting bitter melon, apply a base fertilizer, and after planting, apply a top dressing, but be careful not to over-fertilize bitter melon. Over-fertilizing will cause problems. Generally, the roots absorb fertilizer, but if too much fertilizer makes the concentration too high, it cannot be absorbed, and it easily damages the roots. Plants also have a limit to their nutrient needs; if too much fertilizer is applied at once, it cannot all be absorbed and can only be wasted. The specific fertilizer damage caused by over-fertilizing will be introduced next.

1. Over-Fertilizing

If too much potassium fertilizer is used, fertilizer damage occurs, mainly shown as yellowing and death of the leaves. Using too much fertilizer at once raises the concentration of the soil solution, causing cells to lose water, after which there will be some wilting signs, and in severe cases the roots will be damaged and the plant will die directly. Therefore, when using fertilizer, it must be ensured that the concentration of the soil solution is somewhat lower than the concentration of the cell solution.

2. Incorrect Fertilizing

Fertilizing on the surface without covering it with soil gives poor absorption, and chemical fertilizers cannot be buried deep; they also cannot be placed too close to the roots. Directly using untreated organic fertilizer contains large amounts of pathogens, insect eggs and contaminating components; fertilizing very close to the roots; using too much trace elements, which will resist each other; applying too much nitrogen fertilizer leads to calcium deficiency; using too much potassium fertilizer lowers the absorption of magnesium and boron elements; directly using chemical fertilizer without adding water to dissolve it. The above are all examples of incorrect practices.

3. Reasonable Fertilizing

The root system of bitter melon is not very strong, so less chemical fertilizer can be applied. If it must be used, add water to dissolve it before use. Use more organic fertilizer, but it must be composted and fermented before use. When using organic fertilizer, it can also be dissolved in water during the seedling stage. After the plant grows, it does not need to be dissolved; simply water after fertilizing to help absorption. Fertilizing should use a balanced ratio of major elements. For trace elements, use the few that are most lacking. Soil can be sampled and tested before fertilizing. Fertilizing must be done evenly and mixed thoroughly, and must not be concentrated in one place, as that is not good for absorption.

4. Fertilizing Amount

During the general growth period of bitter melon, use 10 [units] of urea, 4 jin of potassium fertilizer, and 10 jin of monopotassium phosphate per mu of land. Roughly, about 1000 kg of bitter melon requires nearly 12 jin of nitrogen fertilizer, with 2 to 3 top dressings, and 20 jin of compound fertilizer per application. For foliar top dressing, use 0.2% monopotassium phosphate and spray 2 to 3 times. About this much fertilizing is enough; do not use too much.

For fertilizing bitter melon, it is best not to use a fertilizer concentration higher than the soil solution concentration, to apply less chemical fertilizer, more organic fertilizer, and best of all to ensure that fertilizing is not excessive.