Fertilizers are generally inorganic in origin and they supply one / more essential plant nutrients in large proportions.
*Classification of fertilizer -
A. Straight fertilizer -
Fertilizer which supply only one major plant nutrient e.g. Urea
B. Complex fertilizer -
Fertilizer which supplies two or more of the primary nutrients e.g. DAP
C. Mixed fertilizers -
Are the products made by mixing two or more fertilizer e.g. NPK
D. Complete fertilizer -
Fertilizer having all three primary major Nutrients e.g. NPK
E. Low analysis fertilizers -
Having less than 25 % of the primary nutrient e.g. SSP
F. High analysis fertilizer -
Contains more than 25 % of the total primary nutrient e.g. Urea