Fertilizers are chemical compounds given to plants to promote growth; they are usually applied either through the soil, for uptake by plant roots, or by foliar feeding, for uptake through leaves.
Fertilizers can be divided into organic (composed of plant or animal matter), or inorganic (made of simple, non-carbonaceous chemicals or minerals).
Fertilizer Selection
The three primary plant nutrients contained in commercial fertilizers are (N) nitrogen, (P) phosphorus and (K) potassium. These nutrients are represented by the three numbers on every fertilizer bag. A fertilizer labeled "32-10-10" indicated that 32% of the contents is nitrogen (N), 10% of the contents is available phosphorus (P2O5), 10% of the contents is soluble potassium (K2O) and the other 48% is inert filler.
Example: Suppose the soil test recommended that you apply 100 lbs of nitrogen per acre. Using the 32-10-10 fertilizer, you would need to apply 312 pounds per acre (100 lbs of nitrogen divided by 32% (.32) = 312 lbs of fertilizer). |
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'Organic' fertilizers are composed of 'naturally' occurring compounds such as peat manufactured through natural processes (such as composting) or naturally occuring mineral deposits; or in the case of 'inorganic' fertilizers, manufactured through chemical processes (such as the Haber process) or from naturally occuring deposits that have been chemically altered (concentrated Triple superphosphate.
Properly applied, these fertilizers can improve the health, productivity, and appearance of plants as they provide different essential nutrients intended to encourage plant growth.
Bulk Fertilizer
If you are looking for substantial savings on fertilizer, call our Bulk Fertilizer Department at 1-800-274-3389. We offer liquids, such as 28-0-0 and 10-34-0, as well as dry fertilizers, like 46-0-0 and 18-46-0.
Fertilizers typically provide, in varying proportions, the three major plant nutrients: nitrogen, phosphorus, potassium known shorthand as N-P-K); the secondary plant nutrients (calcium, sulfur, magnesium) and sometimes trace elements (or micronutrients) with a role in plant or animal nutrition: boron, chlorine, manganese, iron, zinc, copper, molybdenum and (in some countries) selenium.
Both organic and inorganic fertilizers were called "manure" derived from the French expression for manual (of or belonging to the the hand) tillage, however, this term is currently restricted to organic manure.
Though nitrogen is plentiful in the earth's atmosphere, relatively few plants engage in nitrogen fixation (conversion of atmospheric nitrogen to a plant-accessible form).
It is believed by some that 'organic' agricultural methods are more environmentally friendly and better maintain soil organic matter (SOM) levels.
There are generally accepted scientific studies that support this position.
Regardless of the source, fertilization results in increased unharvested plant biomass left on the soil surface and crop residues remaining in the soil.
Over-fertilization of a vital nutrient can be detrimental as underfertilization. "Fertilizer burn" can occur when too much fertilizer is applied, resulting in a drying out of the roots and damage or even death of the plant.
Organic fertilizers are as likely to cause plant burn as inorganic fertilizers. According to UC IPM, all 'organic' fertilizers, and some specially-formulated inorganic fertilizers are classified as 'slow-release' fertilizers, and cannot cause nitrogen burn
If excess nitrogen is present plants will begin to exude nitrogen from the leafy areas in a process called guttation. |
