All plants need certain basic nutrients to grow. Whilst these nutrients are usually found in the soil, you may find that you need to give your plants an extra feed if the nutrient content is unbalanced or has become depleted. Fertilizers may also be used to promote flowering, fruiting or leaf growth.

Fertilizers are generally applied either via the soil (for uptake by plant roots), or by foliar spraying (for uptake through leaves). They may be organic (carbon based) or inorganic (containing simple, inorganic chemicals).

Fertilizers typically provide, in varying proportions, the three major plant nutrients (nitrogen, phosphorus, and potassium), the secondary plant nutrients (calcium, sulfur, magnesium), and sometimes trace elements (or micronutrients) with a role in plant nutrition, such as boron, manganese, iron, zinc, copper and molybdenum.