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# METHODS OF FERTILIZER APPLICATION

• Broadcasting – random scattering of the fertilizers on the ground.
• Placement method– application of fertilizers in the planting holes.
• Side dressing – fertilizer is placed at the side of the plant within the root zone, in bands or spot-rings.
• Foliar spraying – specially formulated fertilizer solution applied on the foliage in spray form.
• Drip method – applied through irrigation water.

Determination of Fertilizer Rates

Contents of fertilizers are expressed as fertilizer grade or fertilizer analysis.

• Fertilizer grade indicate the guaranteed minimum of the active ingredients (N, P205, K 20) in the mixture.
• It is expressed as a percentage on a weight to weight basis or percentage by weigh

Example 10:20:o means for every 10kg of the mixture there are 10kg of nitrogen, 20kg of P10 5 and 1okg of K20.

Example

A farmer was asked to apply fertilizers as follows:

• 60 kg/ha nitrogen (top dressing)
• 60 kg/ha P205 (in planting hole).
• 60 kg/ha K20. How much sulphate of ammonia (20%) would be required per hectare? How much double super-phosphate (40%) P2O5would be required per hectare? How much muriate of potash (50% K20) would be required per hectare?

Sulphate of ammonia (SA) which gives 60kg/ha N

60/20 x 100 = 300 kg SA

Double super phosphate (40% P2O5)which gives 60kg/ha P205

60/12 x 100 = 150 kg DSP

Muriate of potash (60% K20) which gives 60kg/hK2O

=60/60 x 100 = 100 kg muriate of potash

Example

A farmer was asked to apply fertilizers as follows:

200kg/ha of DSP (40% P205

150kg/ha of muriate of potash (60% K20)

150kg/ha of sulphate of ammonia (20% N)

How much P205 did the farmer apply per acre?

How much K20 did the farmer apply per hectare?

How much N did the farmer apply per hectare?