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Coir compost

I am an old newbe imageso please excuse my silly questions

I am about to start growing trees, shrubs and flowers 

I have got a very small greenhouse in a small hanky sized bit of land and window sills 

I thought the Coir compost would be perfect for me as long as I can grow the above from seeds ...and would it do for bonsai trees

Thank you for helping



Last edited: 09 August 2017 23:03:57



  • josusa47josusa47 Posts: 3,532

    Coir is ground up coconut shells and fibre, great for the producers in the developing world as they can get money for what would otherwise be a worthless waste product.  I go through about eight coir bricks a year.  But it contains scarcely any nutrients for plants.  Some suppliers, eg the Organic Gardening Catalogue, sell sachets of nutrient powder to add.  I also add a double handful of seaweed meal to each brick, to help with water retention.  I don't know if it's suitable for bonsai, I'll leave that for someone else to answer.  It's great for seeds because there are no weed seeds in it, so you know that whatever comes up is what you've sown.  I don't find it so useful for growing bigger plants in pots because it's so light they fall over.

    And I don't think it was a silly question.

    Last edited: 09 August 2017 23:37:38

  • InglezinhoInglezinho Posts: 558

    It's not a silly question, but coir compost, which is made from coconut husks, is very high in taurine, which is toxic to a wide range of plants. I have never had any success with it and don't use it any more. Home made compost is the best but if you can't make enough anything bark-based is good. 

    Good luck


    Last edited: 10 August 2017 01:39:13

    Everyone likes butterflies. Nobody likes caterpillars.
  • Pete.8Pete.8 Billericay, EssexPosts: 7,658

    I wouldn't use coir for general gardening use at all.
    Soil/compost is able to resist changes to the acidity/alkalinty as it has strong 'buffering' properties. i.e. it resists change and keeps itself stable. Coir does not and unless you're very careful it's easy to kill plants. 
    I'd strongly suggest using a seed compost for your seeds, and mpc (multi purpose compost) for the other stuff - I've been very pleased with Grow Wise mpc with added JI
    If you're growing plants in pots long-term, then John Innes 2 or 3 with added grit is your best option.

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Thank you ALL so much ... It is so confusing trying to work out what type of soil for what plants ... Do you know if there is a list anywhere that I can go to please ... 

    Last edited: 10 August 2017 10:59:08

  • Pete.8Pete.8 Billericay, EssexPosts: 7,658

    Most plants will be happy in mpc or John Innes - they're designed to be suitable for most plants.
    If you're planning on growing acers/rhododendrons and the like, they don't like alkaline soil, but that's when they're in the soil in your garden. You can buy ericaceous compost for these plants.
    If you give us some ideas as to what you plan to grow, I'm sure you'll get help here.
    Generally speaking you wont go wrong with MPC and/or JI

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • I would like to grow from seed all sorts of plants that will sell in the community charity shop ... As I live in a flat I want to do it but I have not the space to keep them ... so anything pretty I can get cheap enough to give them to sell .. from seeds to cuttings ... from flowers to shrubs and trees ... Any advice or recommendations would be happily received 

    Thank you all so much for your help 

    Please keep in mind I am a pensioner and I am giving the plants away so Please keep things as cheap as possible

    Thanks again


  • Pete.8Pete.8 Billericay, EssexPosts: 7,658

    If you're in a flat, then I'd not grow trees or shrubs. They take many years from seed and you don't have the right conditions - unless you have a big sheltered balcony?
    Start of with the easy stuff. From seed you can grow most of the half-hardy annuals/perennials  - like marigolds, asters, dahlias, cosmos etc and you can grow lettuce, cabbage etc and sell them as seedlings next spring.
    There's a lot you could grow, you're limited only by the space you have and if you can provide enough light to keep them healthy.

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • punkdocpunkdoc Sheffield, Derbyshire border.Posts: 9,947

    Sorry to disagree, but coir is an excellent growing medium, especially for starting seeds in.

    It is environmentally friendly and is a great soil conditioner, due to its fibrous nature.

    It is recommended by the RHS. and used in their gardens.

    I agree that it does not hold nutrients well, so not good for long term use in pots.

    Southern trees bear a strange fruit
    Blood on the leaves and blood at the root
  • Oh dear Now I am confused .. I thought that the Coir being light and versatile would be perfect for me and I love the thought of using a normally throw away product so is good for the earth ... I am going to do an experiment with it and John Innes compost and compare ... I will first be growing pampus grass from seed as its cheap and should not take too long I hope

  • Pete.8Pete.8 Billericay, EssexPosts: 7,658

    Can I suggest you use mpc rather than John Innes for your experiment.
    Good luck and let us know how you get on.

    I'd guess that both will germinate your seed very well, but using coir for growing-on would not be my recommendation unless you use hydroponic fertilizers from the seedling stage.

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
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