There are many organic fertilisers available but the most important thing is to improve the soil’s structure and fertility before planting. Without this most fertilisers will be of limited benefit because the soil will not be able to hold on to them for long. Organic growing improves the soil, encourages earthworms and good bacteria. The aim is to protect the micro-organisms in the soil by avoiding substances that can damage them. Some “natural” substances are not acceptable because of its affect on soil life, which is important. Some plants are actually quite toxic; for example nicotine (a natural plant product) should not be used as it is too harmful to too many forms of life.
Conventional fertilisers generally contain high concentrations of nitrogen (to stimulate leafy growth), phosphorus (to feed the roots) and potassium (or fruit and seed production) whereas organic fertilisers will contain some of these elements together with good levels of essential micronutrients or trace elements which promote a healthy growth.