• differences between particle sizes of the different fertilizers
(smaller particles tend to accumulate in the lower part of the
fertilizer mass)
• differences between the densities of the different fertilizers
(particles of higher density gather in the lower part of the fertilizer
mass)
• differences between particle shapes of the different fertilizers
(fertilizer particles of spherical shape move more readily in the
fertilizer mass than irregularly shaped particles).
For practical reasons it is assumed that similar size of particles
is a sufficient criterion for selecting solid components of fertilizer
blends [1÷3].