我们是来帮忙的

There are 17 elements that are known to be essential for plant growth and development. Fertilizers (also called plant food elements) are materials produced to supply these elements in a readily available form for plant use. Three of the 17 essential elements, 碳, 氢和氧, are taken primarily from the air and water. Oxygen and hydrogen are obtained by plants from water. Carbon and hydrogen are taken in by the leaves from the air. The other 14 elements utilized by the plant must come from the soil or from added fertilizer materials. (氮, 磷, 钾, 硫, 锌, 铁, 硼, 镁, 锰, 钼, 铜, 钙, 氯, Nickle) Crop removal of these elements, 加上浸出, volatilization and erosion causes the soil fertility to be continually reduced. Plants will have poor color (yellow-green to yellow), poor plant density allowing weed invasion and low plant vigor which increases plants susceptibilities to disease and insect damage. Soil productivity can be maintained by well managed, scheduled applications of multiple element fertilizers.

For plants, macronutrients are essential for growth and overall plant stability. The primary macronutrients are Nitrogen (N), 磷 (P), and 钾 (K). Nitrogen is essential for plant development, since it plays a fundamental role in energy metabolism and protein synthesis. Phopshorus is involved in root growth. 钾 is involved in the regulation of water and the transport of the plant's reserve substances.

Secondary nutrients are those that are still necessary for plant growth- 钙 (Ca), 镁(毫克), and 硫 (S) - just in smaller amounts than macronutrients.

Though micronutrients don’t make the same immediate impact to plant health as the macro and secondary nutrients, they are a key to achieve full balanced nutrition for plants. Plants may only need a small amount of a micronutrient, but a deficiency in the soil can still make a big difference in yield and overall plant health. 这些物质包括硼(B), 锌(锌), 铁(Fe), 铜(铜), 锰(Mn), 钼(Mo), 氯(Cl).