Amounts of N, P and K fertilizers needed by maize intended for fodder production in Southern England

Eighteen field trials were carried out from 1973 to 1975 (inclusive) in Southern England to assess the N, P and K requirement of fodder maize on soils with a wide variation in levels of available N, P and K ranging from low to high. It was only slightly (and not consistently) responsive to the added nutrients, though N, P, and K offtake by the crop was large. Practical considerations for formulating a fertilizer policy for this crop are discussed. Under conditions of low fertility, maximum yields of dry matter may be obtained with 60 kg ha −1 of N and 75 kg ha −1 of both P 2 O 5 and K 2 O, but this practice would deplete reserves of P and K in the soil. This should be rectified later in the crop rotation.