Post on 20-Feb-2015
B Y:D A O - AY E N , C Y R U S
F E L I X , J A C K Y J O H NJ I M E N E Z , J A M E S
Fertilizer Computations
Fertilizer Materials and Calculation
Nutrient Management
Part 1: Understanding the PalayCheck System
Fertilizer – any substance which is added to the soil or applied to the plant to supply the elements essential for plant nutrition
Fertilizer grade – the guaranteed percentage of total nitrogen (N), available phosphorus (P2O5), and water soluble potassium (K2O), in that order, in a fertilizer material
FERTILIZER TERMINOLOGIES
16% N20% P2O5
0% K2O16-20-
0
Total plant food – the total percentage of nutrients (usually of N,P,K and S) in a fertilizer material
17-0-17-12 = 46% total plant food14-14-14-12 = 54% total plant food
Carrier – a material that is necessary to hold the fertilizer element in a form suitable for use
100% – 46% total plant food = 54% carrier
FERTILIZER TERMINOLOGIES
Filler – a material used to provide the fertilizer with the desired amount of nutrient per unit of weight, to make application easier, or to reduce the absorption of water from the air
Fertilizer recommendation – the amount (kg) of N,P2O5, and K2O recommended per hectare
90+30+60 = 90 kg N, 30 kg P2O5, and 60 kg K2O per hectare application
FERTILIZER TERMINOLOGIES
Classification of Fertilizer Materials
According to form
• Natural organic• Chemical or inorganic
• Natural chemical• Synthetic chemical
According to fertilizer elements present
• Single • Incomplete • Complete• Mixed
1. Natural organic – any fertilizer of plant and/or animal origin that has undergone decomposition.
Examples: Commercial organic fertilizer (OF), compost, chicken manure
Organic Matter (%) C:N Ratio
Moisture Content (%)
N+P2O5+K2O (%)
Pure Organic ≥ 20 12:1 ≤ 35 ≤ 7
Fortified Organic ≥ 20 12:1 ≤ 35 > 7
According to form
Commercial OF may either be pure organic or fortified organic:
2. Chemical or inorganic – any fertilizer material which is natural or synthetic product of chemical reaction of certain raw materials.
Natural chemical – rock phosphate, Chilean nitrate of soda, most potassium materials
Synthetic chemical – ammonium sulfate, ordinary superphosphate, ammonium phosphate, complete fertilizer; Urea is synthetic but in organic form.
According to form
1. Single fertilizers – contain only one of the 3 major fertilizer elements (N,P, and K)
Examples: Urea, Ammonium sulfate, ordinary superphosphate, muriate of potash, sulfate of potash
2. Incomplete fertilizers – contain 2 of the 3 major fertilizer elements
Examples: ammonium phosphate, 17-0-17, potassium nitrate, potassium phosphate, urea superphosphate (20-10-0)
According to number of fertilizer elements present
3. Complete fertilizers – contain all the 3 major fertilizer elements
Examples: 14-14-14; 17-7-17; 10-15-15; 12-12-12
4. Mixed fertilizers – contain 2 or more of the major fertilizer elements that are supplied by 2 or more fertilizer materials
Examples: ammonium phosphate + muriate of potash; urea superphosphate (20-10-0)
According to number of fertilizer elements present
Why study fertilizer grades and fertilizer computation?
Consider this:
If Shane needs a teaspoon of sugar to sweeten her juice but there is no sugar available, can she use honey instead?
If Aling Mena does not have enough soy sauce for the adobe she’s cooking, can she add salt? How much?
If Mang Ado needs to apply fertilizer at a recommended rate of 90+30+60 but no complete fertilizer is available, what other fertilizers and how much of it should he use to meet the recommendation?
FERTILIZER
50 kg
14-14-14
Complete fertilizer
14% nitrogen14% phosphorus14% potassium
50 kg sack:
7 kg nitrogen7 kg phosphorus7 kg potassium
Common fertilizer grades in the market
FERTILIZER
50 kg
16-20-0
Ammonium phosphate
16% nitrogen20% phosphorus0% potassium
50 kg sack:
8kg nitrogen10kg phosphorus0kg potassium
FERTILIZER
50 kg
46-0-0
Urea
46% nitrogen0% phosphorus0% potassium
50 kg sack:
23 kg nitrogen0 kg phosphorus0 kg potassium
Other common fertilizers: Ammonium sulfate (21-0-0)Solophos (0-18-0)Muriate of potash (0-0-60)Urea superphosphate (21-10-0)
46% x 50 kg
100
Fertilizer Calculation
Amount of Fertilizer Material (kg)
Recommended Rate (kg nutrient/ha) x Area (ha)=
Percent Nutrient in Fertilizer Material
If Mang Ado needs to apply fertilizer at a recommended rate of 90+30+60 but no complete fertilizer is available, what other fertilizers and how much of it should he use to meet the recommendation?
21-0-00-18-0
0-0-6016-20-0
Use a combination of incomplete and single fertilizer materials
0-0-60
46-0-0
Use a combination of 3 single fertilizers
0-0-60
46-0-0
14-14-14
Use a combination of complete and single fertilizer materials
1 2
3
OPTIONS
Option 1. To calculate the amount of fertilizer materials for 1 ha at the recommended rate of 90 + 30 + 60 using a combination of single fertilizers:
• 21-0-0 (ammonium sulfate)• 0-18-0 (ordinary superphosphate)• 0-0-60 (muriate of potash or potassium chloride)
Therefore, Mang Ado must apply 428.6 kg 21-0-0, 166.7 kg 0-18-0, and 100.0 kg 0-0-60 to satisfy the recommended rate of 90 + 30 + 60.
Amount of 21-0-0 (kg)
90 kg N/ha x 1 ha0.21
= = 428.6
Amount of 0-18-0 (kg)
30 kg P2O5/ha x 1 ha
0.18
= = 166.7
Amount of 0-0-60 (kg)
60 kg K2O/ha x 1 ha
0.60
= = 100.0
16-20-0 (ammonium phosphate 46-0-0 (urea) 0-0-60 (muriate of potash)
Option 2. To calculate the amount of fertilizer materials for 1 ha at the recommended rate of 90 + 30 + 60 using a combination of incomplete and single fertilizers:
Amount of 16-20-0 (kg) 30 kg P2O5/ha x 1 ha
0.20= = 150.0
Amount of 46-0-0 (kg) 90 kg N – kg N from 150 kg 16-20-0/ha x 1 ha0.46=
90 – (150 x 0.16)0.46
= 90 – 240.46
= 660.46
=
= 143.5
Amount of 0-0-60 (kg) 60 kg K2O/ha x 1 ha0.60
= = 100.0
Therefore, he must apply 150.0 kg 16-20-0, 143.5 kg 46-0-0, and 100.0 kg 0-0-60 to satisfy the recommended rate of 90 + 30 + 60
14-14-14 (complete) 46-0-0 (urea) 0-0-60 (muriate of potash)
Option 3. To calculate the amount of fertilizer materials for 1 ha at the recommended rate of 90 + 30 + 60 using a combination of complete and single fertilizers:
Amount of 14-14-14 (kg) 30 kg P2O5/ha x 1 ha0.14
= = 214.3
Therefore, he must apply 214.3 kg 14-14-14, 130.4 kg 46-0-0, and 50.0 kg 0-0-60 to satisfy the recommended rate of 90 + 30 + 60
Amount of 46-0-0 (kg) 90 kg N – kg N from 214.3 kg 14-14-14/ha x 1 ha0.46
=
90 – (214.3 x 0.14)0.46
= 90 – 300.46
= 600.46
= 130.4=
Amount of 0-0-60 (kg) 60 kg K2O – kg K2O from 214.3 kg 14-14-14/ha x 1 ha0.60
=
60 – (214.3 x 0.14)0.60= 60 – 30
0.60= 300.60= 50.0=
Determine the least expensive fertilizer combination that can satisfy the recommended rate (90 + 30 + 60).
21-0-0428.6 kg50 kg/bag= = P
4,714.60x P 550/bag
0-18-0166.7 kg50 kg/bag= = P
1,833.70x P 550/bag
0-0-60100.0 kg50 kg/bag= = P
1,650.00x P 825/bag
TOTAL COST = P 8,198.30
Cost of option 1. combination of single fertilizers:
21-0-0 0-18-0
0-0-60
16-20-0150.0 kg50 kg/bag= = P 2,460.00x P 820/bag
46-0-0143.5 kg50 kg/bag= = P 2,554.30x P 890/bag
0-0-60100.0 kg50 kg/bag= = P 1,650.00x P 825/bag
TOTAL COST = P 6,664.30
Cost of option 2. combination of incomplete and single fertilizers:
16-20-0
0-0-60
46-0-0
14-14-14214.3 kg50 kg/bag= = P 3,471.66x P 810/bag
46-0-0130.4 kg50 kg/bag= = P 2,321.12x P 890/bag
0-0-6050.0 kg
50 kg/bag= = P 825.00x P 825/bag
TOTAL COST = P 6,617.78
Cost of option 3. combination of complete and single fertilizers:
0-0-60
46-0-0
14-14-14
21-0-00-18-0
0-0-6016-20-0
Use a combination of incomplete and single fertilizer materials
0-0-60
46-0-0
Use a combination of 3 single fertilizers
0-0-60
46-0-0
14-14-14
Use a combination of complete and single fertilizer materials
THANK YOU VERY MUCH!!!