Plant ash is the ashes of burning herbs and woody plants. Because plant ash is the ashes of burning plants, almost all the mineral elements contained in plants are in plant ash. Plant ash is light and alkaline, so it is easy to float with the wind when it is dry, and it is easy to float with water when it is wet. Plant ash can be used as fertilizer, and reasonable application of plant ash can promote plant growth.

Due to the small quantity and light weight of plant ash, alternative methods are often used to obtain plant ash in agricultural production. The specific method is: pile up some vegetation with clay blocks, light it from the middle with kindling, let it smolder until it burns out, then mash the burnt soil and cool it before use. This process is called burning ash. The fire ash treated in this way is not only large, but also simple to operate, and it is not easy to lose when it meets water and wind, and the effect is very good.

Plant ash contains a variety of minerals, which can not only be used as fertilizer, but also play a role in preventing and controlling some diseases and insect pests. There are two ways to apply fertilizer, one is to make base fertilizer and the other is to make foliar fertilizer. Plant ash can be used as base fertilizer, seed fertilizer or topdressing, and its aqueous solution can also be used for topdressing outside roots.

It should be noted that plant ash is an alkaline fertilizer, which can be used in neutral soil, especially acidic soil, but it cannot be used in alkaline soil, nor can it be mixed with ammonium sulfate, ammonium chloride, ammonium bicarbonate, ammonium nitrate and other nitrogen fertilizers to avoid reducing fertilizer efficiency. Nor can it be added to human and animal manure, otherwise ammonium nitrogen will become ammonia and volatilize, reducing fertilizer efficiency.