Feeding plants

[HKCambridge]

I have some plant food which is recommended for tomatoes, chillis, courgettes etc. However at the moment I am only growing herbs and salads, turnips, brassicas and radishes.

Is my existing plant food suitable, or should I get something else? Do all these things need feeding, or are some fine without?

Also my current plant food is a year old because I've moved house and I left it a while before re-starting the garden. Will the food still be effective after this amount of time?

[Two_Sheds]

Herbs & salads don't need feeding, at all. Nor radishes. They are all fast-growing and don't need food.

The general rule is Nitrogen for leafy crops; Phosphorus for root crops, and Potash /Potassium for fruiting crops like tomatoes. Here's more info: PlantAdvice.co.uk - FAQ - What does NPK mean on fertiliser packets?