An organic fertilizer is basically derived from something that once lived. For instance ‘Blood, Fish and Bone’ is precisely what it says; but dried and crunched up. Farmyard manure should need no explanation! Some liquid fertilizers/feeds are derived from seaweed....

Generally speaking, they are slower acting than synthetic (man-made) fertilizers - no bad thing - and usually have a beneficial effect upon the soil, as well as feeding the plants. ‘Blood Fish & Bone’  is my favourite; the dried blood soon dissolves ready for the plant to feed upon. The fish is the next to rot down, followed by the crushed bone. A veritable three course meal for the plants to feed upon! Bonemeal is one of the best fertilizers for long term growth in shrub borders and flower beds. Great for fruit crops as well.

There are those who swear by the use of organic fertilizers. It is interesting to note that most professional growers do not use them! 

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