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HOW TO READ FERTILISER LABELS

Fertilisers are chemicals or natural substances which are added to soil or land to increase its fertility.  Fertilisers assist with plant growth and promote resistance to disease.

Different plants have different specific nutritional needs, but there are three main macro-elements required:  Nitrogen (N), Phosphorus (P) and Potassium (K).

NITROGEN (N) – the leaf-maker.  Nitrogen stimulates the growth of leafy vegetables.  It also helps improve the leaf colour in lawns and it increases the size of evergreen plants.

PHOSPHORUS (P) – the root-maker.  Phosphorus stimulates early root formation.  It’s therefore essential in soil which is used for sowing seeds and growing young plants.  Phosphorus also enables plants to resist disease and encourages winter hardiness.

POTASSIUM (K) – the flower and fruit maker.  Potassium, or potash (K) improves the quality of flowers and fruit as well as the flavour of fruit and vegetables.  Essential for photosynthesis, potassium also makes plants more resistant to temperature extremes and drought.

Fertilisers are named according to the three macro-elements mentioned above, which are represented as N:P:K (%)  For example:  2:3:2 (14) contains 2 parts N (nitrogen), 3 parts P (phosphorus) and 2 parts K (potassium).  The number 14 indicates the total percentage of available NPK in the fertiliser bag.  Fillers are added, mainly to assist with the spreading of the nutrients evenly in the soil and to avoid the nutrients burning the roots and plants.

SR indicates that the formulation is a Slow Release fertiliser – nitrogen is released slowly into the soil over time.

SR* indicates that the formulation is a Sustained Release one.  Nutrients are released at a specific rate over the specific period of time.