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17 September 2014
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how to be a gardener - The complete online guide

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5 - Feeding
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Fertilisers are basically divided into two groups:

Organic: from natural sources like plants, animals or naturally occurring rock.

Inorganic: man-made, manufactured ‘chemical’ feeds.
Plants don’t care where their nutrients come from, just so long as they get enough, but from a gardeners’ point of view, organic fertilisers have the edge because they encourage soil bacteria, which help keep soil healthy.
By law, the amounts of nitrogen, phosphorus and potassium a fertiliser contains must be stated on the packaging. So if a packet is labelled 6:4:4, it means that in every 100 grams of fertiliser, there is 6 grams of nitrogen (N) and four grams each of phosphorus (P) and potassium (K). Note that the order is always the same, ie NPK.
This N:P:K ratio also helps you choose the right fertiliser. If the ratios are about the same, it is a general-purpose fertiliser and will aid all round growth. If the fertiliser has a higher ratio of:
Nitrogen - it will encourage leafy growth
Phosphorus - it will encourage root development
Potassium - it will encourage fruit and flower production
5. Caring for your garden

 Types of feed
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