Principles of application
Diammonium phosphate is applied as a basal and starter fertilizer. It is suitable for all types of soils. Diammonium phosphate effectiveness increases with uniform distribution in the soil layer during broadcast tillage or in tilled strip. At sowing application with diammonium phosphate is useful in case of appropriate granules placement (it should be couple centimeters deeper than placement of seeds). Fertilizer placement at the same level with seeds has not toxic influence on it, but limits nutrients intake.
Regardless of water availability, side dressing is less effective than at sowing and sowing fertilization due to low migration capability of phosphorous. It should be understood that the root system deepens faster than the phosphorus compounds. Side dressing with diammonium phosphate in growing season is applied to at least 8-10 centimeters in depth with sufficient water availability. Side dressing of fruit and berry crops is applied in spring before active vegetation or in autumn after active vegetation directly followed by incorporation into the topsoil surface layer.
If use diammonium phosphate as the starter it is required to add one more fertilizer which includes nitrogen in its composition to strengthen the plant.
Application of diammonium phosphate after the germination of seeds does not influence phosphorous side dressing. The reason for this is that phosphorous is retained by soil grains and as a result complicates its horizontal movement. When rainfall occurs phosphorous can reach the depth of 5-6 cm. Therefore, when applying diammonium phosphate, it is better to apply it 5-6 cm below the sowing depth.
Diammonium phosphate application doses are calculated by taking into account soil phosphorous availability, crops’ phosphorous demand and estimated yield.