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Is organic fertilizer OK?

Hi - I have been reading a lot about how adding artificial NPK fertilizers to the soil can kill off all of the natural fungus, bacteria and micro-organisms that would normally help to fertilize plants.  I garden organically and this would not be very desirable for me on principle, but also because it apparently creates a cycle where the garden needs the artificial NPK fertilizer more and more each year as all the natural fertilizers are killed off.  I have bought some 'organic feed', but I noticed that it still has an NPK rating on it.  Is this OK to use in an organic garden - i.e. will it preserve the natural micro-organisms?  Or does it just mean that it has been created using organic methods but will still kill off the natural fertilizers like artificial NPK fertilizers?  Thanks for any help - I don't understand this topic as much as I would like!


  • sotongeoffsotongeoff Posts: 9,802

    All fertilisers organic or not will contain NPK for plant growth-they need it-we are made up of chemicals- as is everything

    I am not sure that answers your question thoughimage

  • BobTheGardenerBobTheGardener Leicestershire, UKPosts: 11,391

    The very act of gardening changes the natural balance of the soil, but without doing that we would be very limited as to the things we could grow.  I think what you're reading is similar to the argument that taking vitamin pills provides things the body needs, but may reduce the bodies capacity to produce them itself from ingested food.  My opinion of what 'organic' gardening means is using no artificially manufactured chemicals such as pesticides and herbicides, but those made from plants are OK.  In practical terms, to increase soil fertility organically means making your own compost and adding animal manure, which is high in Potassium and Phosphorus (ie K and P.)  The N (Nitrogen) will come from anything green you place in the compost.  Dead material such as dry leaves and stems provides almost nothing in terms of nutrients, but improves soil structure.  Growing a large clump of comfrey, harvesting it several times a year and adding it to your compost heap is an excellent way to get the Nitrogen, as well as providing several trace nutrients comfrey extracts from the subsoil via extremely deep roots. It is the naturally occuring bacteria and fungi in your compost heap which break down organic matter and release N, P and K.

    I'm not sure if that answers your question either, though.



    A trowel in the hand is worth a thousand lost under a bush.
  • As the others have said all fertiliser has NPK. In bought fertiliser it usually shows the ratio of each. Depending on what you're growing/time of year/make up of your soil will determine which type you need. If you garden organically then you wouldn't want to be using artifical fertilisers. However, fertilisers such as Bonemeal, Blood,fish and Bone, seaweed, poultry manure are classed as organic. They'll have a different NPK ratio depending on the type. They also break down at different rates. I use a slow release fertiliser, such as bonemeal, which is rich in N (Nitrogen), when I'm planting up. Liquid Seaweed is good to give plants a quick boost, especially plants in pots. I also use part of my nettle patches to make liquid fertiliser as it's rich in N. Stinks a bit though, so don't do what I did one year and "cooked" it too near my back windows. The neighbours weren't too happy either image

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