Foliar nutrition of crops: Facts, Myths and Perspectives

Foliar fertilisers are increasingly used in agriculture and new commercial products are continuously released by fertiliser companies as a result of the increasing demand. There is indeed abundant evidence showing the beneficial effects of applying foliar fertilisers as a complementary strategy to soil treatments in terms of improved plant metabolism, yields and quality of crops. However, the current lack of scientific knowledge on many factors associated with the effectiveness of foliar treatments limits the reproducibility of the results after spraying fertilisers to different crops under different growing conditions. Additionally, the limited transfer of technical know-how from the scientific foliar uptake community to the agricultural sector supports the exiting “spray and pray” attitude when applying a foliar nutrition treatment to a crop (i.e., anything may happen).

Thereby, and in light of the current foliar fertilisation scenario, the following questions are raised:

1. which foliar fertilisation facts are currently clear for researchers?,
2. which kind of traditional believes are not helpful to ensure the effectiveness of a foliar treatment?, and
3. what is the future of foliar fertilisation?