Do tomatoes need fertilizer?

Foliar Feeding is a relatively new, slightly controversial technique of feeding plants by applying liquid fertiliser directly to their leaves. In some cases, a dramatic example being tomatoes, this goes against long-standing strictures against ever allowing the leaves to get wet. While the conventional wisdom is "don't even spray your tomato plants, only water them by soaking the ground beneath", modern gardening techniques strongly recommend spraying the leaves of a tomato plant with fertiliser, as part of the normal fertilisation routine.