Watch your P's & K's for cereals

Why potash is important

Potash affects both yield and quality of grain as well as other aspects of plant vigour and health. Cereal crops need at least as much, if not more, potash than any other nutrient including nitrogen. Potash is needed in such large amounts because it regulates water and nutrient movement in the plant. The practical implications of shortage are:

		Low yield		Poor quality
		Inefficient N response		Increased risk N loss
		Reduced 1000 grain/specific weight		Reduced grain ripening period
		Lower grains per ear		Poorer grain sample
		Weaker straw		Increased lodging risk
		Increased susceptibility to drought		Increased disease susceptibility

N:K partnership

Cereals require a balance of nitrogen and potash to obtain full yield response to applied nitrogen. If there is a shortage of potash, nitrogen is not taken up or used efficiently and some may be lost with risk to the environment. Careful optimisation of nitrogen is a waste of time if potash supplies are not adequate.

Effect of potash on nitrogen response