In recent days, farmers in winter wheat growing areas have begun to spray herbicides. A farmer friend asked: Will it affect the efficacy of a rainy day soon after the herbicide is applied to the wheat? Do I need to respray?

Whether it is herbicides, insecticides, or fungicides, you must decide when to spray according to the weather! So, what if there is an emergency? It is predicted that there is no rain, but it is raining. In this case, if the herbicide is sprayed, do I need to re-spray it?

 If you really encounter it, it depends on the following two aspects:

　　 Situation 1: Rainfall

　　 Soon after the herbicide has been applied, if you encounter a pattering shower that will stop for a while, you don’t need to spray it again. This kind of light rain has little effect on the efficacy of the herbicide.

　　Scenario 2: Duration

　　 If it is a sudden heavy rain or heavy rain that lasts for a long time, you need to consider respraying herbicides.

　　 However, if the light rain lasts for a few hours or even longer, even if the rainfall is not heavy, but it lasts for such a long time, it needs to be sprayed again.

　　 In addition to considering whether to re-spray, but also to consider the situation of phytotoxicity.

　　 When it rains, the roots of the wheat plant are relatively concave, which is likely to accumulate water. If the liquid medicine accumulates too much water in the roots, the concentration of local herbicides will increase, and it is prone to phytotoxicity, so you need to pay attention to drainage measures.