Chemical Fertilizers

Chemical and natural fertilizers are compounds given to plants to promote growth; they are usually applied either via the soil, for intake by the plant’s roots, or for intake through the plant’s leaves. Fertilizers can be organic, that is a fertilizer composed of completely organic matter, or inorganic, which is made of simple, inorganic chemicals or minerals. These things can be naturally occurring like in a peat bog or found as mineral deposits. Or these fertilizers can be manufactured through natural processes, such as composting, or a chemical process like the Haber process.

Fertilizers usually provide, in varying amounts, the three major plant nutrients. Nitrogen, Phosphorus, and Potassium, and the secondary plant nutrients calcium, sulfur, magnesium, and some will provide trace elements that also play a role in plant nutrition: boron, chlorine, manganese, iron, zinc, copper, and molybdenum.

In the past, most fertilizer was of the very organic variety…namely manure…which is the term applied to cow or horse fecal matter. Now-a-days most farmers prefer to use naturally occurring inorganic fertilizers.

Most fertilizers used on large farms contain only one or two macronutrients and are generally of the inorganic variety. These types of fertilizers are intended to be applied infrequently and either just before seeding or while the seeding is taking place. Some examples of agricultural fertilizers are granular triple superphosphate, potassium chloride, urea, and anhydrous ammonia.

Due to the availability of certain materials that make up certain brands of fertilizer, and of course, the high cost of shipping, these sort of things leads to use of locally available materials. Or those from the closest and cheapest source, which may vary due to transportation by train, boat, or truck. Basically this means that a particular nitrogen source may be popular in one part of the country while another is quite popular in another part of a country because of availablity of the certain resources.

Horticultural fertilizers, on the other hand, are formulated to produce balanced fertilizers that also contain micronutrients. The 18-51-20 is a horticultural fertilizer formulated with high phosphorus to promote bloom development in ornamental flowers. Horticultural fertilizers may be water-soluble which is an instant release tupe of fertilizer, or some what insoluble, also known as controlled release fertilizers. These often look like little spikes that are pushed into the ground next to trees, shrubs, etc. Controlled release fertilizers are also referred to as sustained release or timed release. Most controlled release fertilizers are for applying about every 3-6 months. Of course the amount depends on the amount of water, growth, and various other conditions the plants may receive, whereas water-soluble fertilizers must be given about every 1-2 weeks; but water soluble fertilizers can be used during every watering if dilute.