1. Lesson 4 – Fertilizing Soils
Advanced Plant Science
Mr. Dieckhoff

2. Where are we going… Types of Fertilizers Forms of Fertilizers
Fertilizer Formulations
Fertilizer Application Techniques
Fertilizer Application Time Periods
Calculating Fertilizer Application Rates

3. Types of Fertilizers Mineral Organic
Limestone – good source of calcium, magnesium, and sulfur
Phosphorus – phosphate rock – P2O5
Potassium – potash – K2O
Organic
Manures
Chemical (inorganic) – manufactured from non-living sources
Formulations of N, P, K

4. Forms of Fertilizer
Fluid
Pressurized Liquids
Dry
Slow Release

5. Fertilizer Formulations
Fertilizer Grade
%N - %P - %K
To determine pounds of nutrient, take % x total pounds of fertilizer

6. Calculating Nutrients in Fertilizer
How many pounds of nitrogen are in a 20 lb bag of fertilizer?
How many pounds of potassium are in a 10 lb bottle of fertilizer?
How many pounds of phosphorus are in a 50 lb tub of fertilizer?

7. Calculating Nutrients in Fertilizer - Answers
How many pounds of nitrogen are in a 20 lb bag of fertilizer?
4 lbs
How many pounds of potassium are in a 10 lb bottle of fertilizer? lbs
How many pounds of phosphorus are in a 50 lb tub of fertilizer? lbs

8. Fertilizer Application Techniques
Broadcasting
Soil Injection

9. Fertilizer Application Techniques
Banding
Side-dressing

10. Fertilizer Application Techniques
Top Dressing
Foliar

11. Fertilizer Application Techniques
Fertigation

12. When should fertilizer be applied?
Soil Temperature – above freezing until 85 degrees
Moisture – dry soil better
Single vs. Split application
Mobile (leaching) nutrients
Fall – not in sandy soils, spread anhydrous ammonia
Winter – anhydrous ammonia
Spring – apply when planting
Summer – side dressing & fertigation when needed

13. Fertilizer Rate Calculations
To calculate amount of limestone:
Lime is applied in pounds of ENM (effective neutralizing material)
ENM value from soil test divide by ENM of limestone
Example, if soil test calls for 1,450 lbs/ac and dealer guarentees 400 lbs ENM per ton:
1,450 lb/ac divide 400 lbs ENM/ton = 3.63 ton/ac

14. Soil Test Recommendations:
P = 70
K = 50
Total acres to spread is 75.
Fertilizer Sources and Costs per pound:
Diammonium Phosphate
$ 0.07
Ammonium Nitrate
$ 0.14
Potassium Chloride
$ 0.08
Spreading charge is $3.00 per acre.

15. Match the definition on the left to the term on the right.
1. ____ Application technique for anhydrous ammonia.
2. ____ Method used to fertilize pastures.
3. ____ Used when planting to stimulate seed germination.
4. ____ Dry fertilizer placed to each side and below seed.
5. ____ Spreading dry fertilizer over soil prior to planting.
6. ____ Application of fertilizer in irrigation systems.
7. ____ Fertilizer applied directly to leaves of plants.
8. ____ Fertilizer applied 6 to 8 inches from the plant row.
a. Broadcasting
b. Soil injection
c. Banding
d. Starter applications
e. Side-dressing
f. Top-dressing
g. Foliar
h. Fertigation