Soil Nutrients by cTwFyL


									               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
• Sulfur
• Calcium
• Magnesium
What are the Micronutrients?
•   Iron
•   Boron
•   Zinc
•   Manganese
•   Copper
•   Molybdenum
•   Chlorine
What are the 16 essential
• 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
  – deficiency: stunted growth, purple color in
• Potassium: mostly regulatory
  – deficiency: stunted growth, mottled leaves
Are there non-essential plant
nutrients that need to be

  • 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
• 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?
• 10% of 50# = 5# Nitrogen
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
• inert materials (filler)
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
  – $1.86
A similar analysis of "Farmers Grade
  Fertilizer" runs about $0.40 per pound of
  actual nutrient.

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