Di-Ammonium Phosphate (DAP)

  • High analysis source of phosphorus.

  • N:P ratio of 1:1 makes it an effective source of nitrogen.

  • DAP releases free ammonium. Nitrogen in the ammonium form resists leaching and is a slower release form of nitrogen.

  • The free ammonium gives a higher pH reaction immediately around the granule.

  • The low cost of nitrogen in DAP makes it a cost effective source of nitrogen if Phosphorus is also required.

Typical Analysis
N%
0
P%
0
K%
0
S%
0
Zn%
0
N%P%K%S%Zn%
1820.201.50
  • Chemical name

    Diammonium phosphate

  • Crop Segments

    All

  • Features

    High analysis nitrogen and phosphorus contained in every granule.

  • Quality & Handling

    Nominal 2-4mm size granule, free flowing product. Bulk density 0.9 tonnes per cubic metre.

  • Blending

    Can be blended with most products and trace elements.

Image
Manufacture

Ammonia gas is combined with phosphoric acid in a ratio of 1:1, granulated, dried and screened.

Uses

One of the major cropping fertilisers used in Australia as a source of both phosphorus and nitrogen. The high phosphorus content makes it a true high analysis fertiliser. DAP and DAP blends are used on a range of crops in broad-acre farming, cereals, sugar cane, sowing pastures, dairy pastures, fodder crops and also in horticultural crops; for example, vegetables and tree crops.

Storage & Handling
  • Does tend to take up moisture, both in storage and in the field.
  • Storage in a bulk shed is the preferred storage method. Covering with a tarp may reduce any moist air uptake.
  • The use of augers may damage the fertiliser and increase any handling problems.
  • Do not leave exposed to moist air.
  • Either fill or empty (completely), the drill or air-seeder fertiliser box overnight.
  • Cover seeding equipment with a tarp.
  • Raise the equipment tynes from the soil to stop moisture moving up the tubes.
Restrictions
  • For sowing there is little risk of affecting germination, even at high rates. The general rule of a maximum of 20kg/ha of nitrogen at seeding of cereals should be used.
  • When applying DAP, the fertiliser should be banded 5cm away from the seed, either below or to the side. DAP is low in sulphur – 1.5%. It is not recommended for high sulphur requiring crops such as canola, unless blended with sulphate of ammonia.
  • Do not store in silos.