What are the key periods and precautions for applying pesticides to fruit trees?

In recent years, fruit prices have been climbing steadily, which has delighted many fruit growers. However, although fruit cultivation offers good economic returns, managing it is not so simple. To reduce the invasion of pests and diseases, a certain amount of pesticide is often sprayed. So how many key periods are there for applying pesticides to fruit trees? What are the precautions?

I. How many key periods are there for applying pesticides to fruit trees?

1. The stage when the young buds of fruit tree saplings swell. Also called the bare-pole spray, at this stage a relatively high-concentration insecticide should be sprayed, thoroughly covering both the tree and the ground beneath it, mainly to prevent overwintering pests and pathogens of the fruit trees.

2. The flower bud stage. At this stage, insecticides and fungicides need to be sprayed, mainly to prevent flower rot.

3. One week after petal fall. Pesticides sprayed at this stage mainly prevent aphids, pear psyllids, red spider mites, and so on.

4. After fruit picking, in the early leaf-fall stage. This stage is mainly to reduce the occurrence of overwintering pests, so that pest problems will be fewer the following year. Note that when mixing sprays, acidic and alkaline agents should not be used together.

II. What are the precautions for applying pesticides to fruit trees?

1. Using pesticides blindly without distinguishing tree species

When using pesticides, growers should distinguish between different varieties of fruit trees. For peach trees, for example, a relatively sensitive agent is phosphamidon; stone fruit trees are very sensitive to trichlorfon; pear trees are very sensitive to Bordeaux mixture, Fuxing, and so on. If pesticides are used indiscriminately without distinguishing varieties, it will cause relatively serious harm to the fruit trees.

2. Not having a clear understanding of the concept of mixing pesticides

Generally speaking, some pesticides can be mixed together for spraying, but some are indeed unsuitable and cause certain harm to fruit trees. For example, when lime sulfur mixture and Bordeaux mixture are mixed, water-soluble copper increases, and spraying it on fruit trees can easily cause phytotoxicity.

Generally, only after ten days of spraying lime sulfur mixture can Bordeaux mixture be sprayed; if Bordeaux mixture has been sprayed, it generally takes one month before lime sulfur mixture can be sprayed. In addition, Bordeaux mixture cannot be mixed with agents such as thiram and tuijunte. If mixed with organophosphorus pesticides, it can be freely combined without too many requirements.

3. Not spraying according to weather changes

When spraying pesticides on fruit trees, we should spray according to weather changes, so we should pay timely attention to the weather forecast. If it is going to rain that day, do not carry out pesticide spraying.

4. Do not spray during drought or when temperatures are low

We should know that the best temperature for using pesticides is between 20 and 30 °C, as the effectiveness is better at such temperatures. If conditions are drought, low temperature, or high temperature, the effectiveness may not be achieved, and the fruit trees will still suffer from pests and diseases.

In summary, using pesticides in fruit tree cultivation is also a field of knowledge. We should use them according to the instructions on the agent, and not blindly mix them ourselves, which may lead to reduced fruit tree yields, environmental pollution, and other problems.