First, the dilution of repeated spraying of pesticides depends on specific products and rainfall. With each continuous rainfall, the efficacy of pesticides will be lower and lower. The next day's rain will not completely eliminate the efficacy, but it will indeed reduce the efficacy. Compared with the slow drizzle that lasts for several hours, the heavy rainfall in a short time will cause the loss of pesticide efficacy to a greater extent.
Although there are some granular pesticides, the effect is actually better in the rain, which will be activated by rain and immersed in the ground. However, after several heavy rains, most pesticide sprays will become very thin. In the rainy season, sometimes repeated spraying is used to ensure the efficacy. Generally, the more it rains, the faster it sprays.
Second, choose pesticides with good rain tolerance. Some pesticides take effect quickly, can penetrate plant leaves in a short time, and are effective for any growing plant. In this case, when the rain dilutes the pesticide, the quick-acting pesticide has solved the problem, so the rain will not have a significant impact on it. Especially in the rainy season, we never want to use a pesticide that takes several weeks to take effect. There are other types of pesticides that can achieve waterproof effect.
Third, pay attention to the weather changes. Before the rainy season comes, you should pay attention to the weather changes and spray pesticides earlier and more timely.
In addition, it should be noted that the application of pesticides in rainy season is more likely to cause soil and water pollution. When it rains, most pesticides are either immersed in the ground or flow into streams along the slope. This situation will be more serious when there is a lot of rain in a short time.