Soil Nutrients Original by Casey Osksa Modified by Georgia Agricultural Education Curriculum Office July, 2002
What nutrients do plants get from the air and water? Carbon Hydrogen Oxygen
What are the Primary Nutrients? Nitrogen Phosphorous Potassium
What are the Secondary Nutrients? Sulfur Calcium Magnesium
What are the Micronutrients? Iron Boron Zinc Manganese Copper Molybdenum Chlorine
What are the 16 essential nutrients? C HOPKNS Ca Fe Mg B Mn Cu Zn Cl Mo
Functions of Primary Nutrients and the deficiency symptoms? Nitrogen: other than water, most important, determines rate of growth deficiency: yellowing of leaves Phosphorous: needed most during germination and during fruit/seed formation deficiency: stunted growth, purple color in leaves Potassium: mostly regulatory deficiency: stunted growth, mottled leaves
Are there non-essential plant nutrients that need to be considered? Yes, iodine and cobalt are essential in animals but found in plants
Why is a knowledge of soil nutrients necessary? maximize yield maximize profit maintain soil fertility
How do you determine soil fertility? soil testing manage organic matter fertilize
What is Fertilizer Analysis? it is the amount of the different nutrients found in a fertilizer the amount is listed as a percent it is ALWAYS listed Nitrogen-Phosphorous-Potassium (N-P-K) a fertilizer labeled 10-15-10 is 10% Nitrogen, 15% Phosphorous, and 10% Potassium if there is a fourth letter it is for Sulfur
How many pounds of Nitrogen are in a 50# bag of 10-15-10?
Pounds of Actual Nutrients in a 50# bag of 10-15-10? add up 10+15+10 = 35% nutrients or 17.5#
What is the other 65% of this bag? inert materials (filler)
Analysis A hobby gardener buys a bag of "Scott's Turfbuilder" uptown for $31.95. The bag weighs 62# and has an analysis of 22-3-3-10. How many pounds of actual nutrients? 17.2# What is the cost per pound of actual nutrients? $1.86
Analysis A similar analysis of "Farmers Grade Fertilizer" runs about $0.40 per pound of actual nutrient.