1. Soil fertilisation
1.1 Base fertiliser
1.1.1 Time of fertiliser application
Apply before or at the time of crop planting. For example, before sowing maize in spring, the land is ploughed first, and then calcium ammonium nitrate is evenly spread before sowing.
1.1.2 Fertiliser application amount
It depends on the soil fertility status and crop type. Generally speaking, for soil with medium fertility, apply 20 - 30 kg per mu (666.7 square meters). For crops that require more fertiliser, such as bananas and other fruit trees, about 0.5 - 1 kg per plant can be applied.
1.1.3 Fertiliser application methods
Spreading or strip application can be used. When spreading, the calcium ammonium nitrate is evenly spread on the soil surface, and then the fertiliser is mixed into the soil by tilling or rotary ploughing to a depth of 10 - 20 cm. Strip application is to make a furrow on both sides of the planting row, apply the fertiliser into the furrow, and then cover the soil, this method is conducive to the absorption of fertiliser by the root system of the crop.
1.2 Fertiliser application
1.2.1 Fertiliser application time
Carried out during crop growth, according to the growth stage of the crop to determine the specific time. For example, fertiliser tracing in wheat pulling period, cotton bud stage and other key growth stages.
1.2.2 Fertiliser quantity
The amount of fertiliser is usually less than the amount of base fertiliser. For example, for wheat fertiliser, 10 - 15 kg per mu (666.7 square meters).
1.2.3 Fertiliser application method
Fertiliser can be applied either in holes or in strips. Hole application is to dig holes around the crop plants, put the fertiliser into the holes, and then cover the soil. Strip application is to open a shallow furrow between the crop rows to apply fertiliser and then cover the soil, care should be taken to avoid direct contact with the crop root system to prevent root burning.
2. Foliar application
2.1 Solution preparation
Generally, calcium ammonium nitrate is prepared into a 0.5% - 1% solution. For example, weigh 5 - 10 g of calcium ammonium nitrate and dissolve it in 1 litre of water.
2.2 Spraying time
Choose early morning or evening for foliar spraying. Because the temperature is lower at this time, the leaf stomata are open, which is conducive to the absorption of fertiliser, and can reduce the loss of fertiliser due to evaporation at high temperatures and burns on the leaves.
2.3 Spraying frequency
Depending on the growth of the crop, generally every 7 - 10 days spraying, the whole reproductive period spraying 2 - 3 times. For example, during the fruiting period of tomato, it can be sprayed 2 times to improve fruit quality.
2.4 Precautions
When spraying, make sure that the solution is evenly sprayed on both front and back sides of the leaves, but avoid spraying too much during the flowering period of the crop so as not to affect pollination. At the same time, pay attention to the weather forecast to avoid rain within a short period of time after spraying, if rain need to re-spray.