Manure
Another natural and key source of fertilizer for our site on Arda may be manure. This is all natural, but contains many minerals and "healthy" ingredients for plants, trees, and organic life to survive. If it comes to it, we may have to resort to waste and compost piles as the main source of Phosphorous, Nitrogen, and Potassium.
Some more modern formulas for mass produced fertilizers include Ammonium nitrate (NH4NO3), Calcium chloride (CaCl), Calcium nitrate (CaNO3), Potassium chloride (KCl), Potassium nitrate (KNO3), and Potassium sulfate (K2SO4 ). These fertilizer compoiunds are mass produced in concentrations and sent to farmers all over the world.
pH is also an important part in growing crops. You have to have a firm understanding of how pH will affect the crop you are trying to grow. The acid levels of the soil determine which crops can grow in that particular type of soil. 1-3 pH level is very acidic and acidic fruits such as lemons can grow there, 4-7 acidic level is neutral and most plants seem to thrive in this acidic level and environment, and greater than 7 is comparable to a desert environment where you do not see too many plants grow or thrive.
Figure 2 (how plants take in nutrients)