Organic and Environmentally Friendly Soil Amendments Coir

Many gardeners are discovering the value of using coir instead of peat moss when amending their garden soil for the upcoming spring planting season.  What is coir?  Coir (pronounced COY-er) is a by-product of coconut harvests. It is the pithy material found between the fibres of the hard internal shell and the outer coat of the coconut. The main suppliers of coconuts are Indonesia, the Philippines, India, and Brazil.   Coir was first used as a growing medium in India and China.  The Dutch discovered coir in the 1980’s and passed on their knowledge to Dutch hydroponic rose growers in Canada and the USA.  Coir is also used as hanging basket liner, and in the production of rough door mats, brooms, twine and brushes. Bog peat takes over 200 years to renew itself.  Coconut trees produce new coconuts on a monthly basis. The maximum age of a coconut palm is 100-120 years. 

The advantages of using coir as a soil additive instead of peat moss are many.  Like peat, coir is a natural product that is made up of cellulose fibres that aerate the soil.   It highly improves water retention, drainage, and helps to loosen clay- based soils.    


Peat breaks down quite quickly requiring yearly applications.  Coir is a very durable biodegradable organic material.   It begins to degrade after two years and at a very slow rate.  Coir can be added to indoor and outdoor soil mixes, vegetable and flower beds.

Coir rehydrates easily; holding up to 8 times its own weight in water.   It is sold in bricks that need to be rehydrated in a wheel barrow and then can be mixed with other soil amendments or existing soil.  Use 3-4 L of warm water.  Wait 30 minutes then mix the coir until it feels like regular soil. You may need to break up the brick to move the process along and possibly more water. 

Peat helps to acidify alkaline soils (pH of 3.5 – 4.5).  The pH of coir is near neutral (5.7-6.5). Coir can have a high salt content so it is best to thoroughly rinse with more fresh water after rehydration.  It is high in phosphorous (P) and potassium (K).

You can find coir seed starting kits on our shelves at Floral Acres.  It also comes in brick form, coir - based seedling pellets (discs), and small 5cm.and 10 cm. diameter pot sizes.

Coir pellets/discs are housed within a biodegradable net.  Place one or two seeds into the center of the pellet before or after hydration.  Carefully pour warm water into the tray as per package directions.  The pellet will expand, encasing the seed. Seeds can be started in the 5 cm., 7 cm. or 10 cm. pot size as well.  When it comes time to transplant your seedlings out into the garden you can snip off some of the coir in a few areas of the pellet/pot. If you see roots coming out of the coir pellet/pot do not snip the sides.


Worm Castings

Gardeners have long known the advantages of having earthworms populate their garden  soil.  As earthworms dig deep into the soil, the oxygen content of that soil increases.  Their tunnels and trails let in air and water.  Adding organic matter such as compost will attract earthworms to your garden. Add some coffee grounds to your compost and the earthworms will come from near and far.  They love coffee grounds!   Earthworms prefer a neutral pH soil but can live in soil with a pH between 5 and 8.

Worm castings are the unprocessed manure of earthworms.  They contain some nitrogen, phosphorus, potassium, and 60 micronutrients!   The castings are high in organic matter, good bacteria and slowly add those essential micronutrients to the soil.  Worm castings can also be used in tropical soil for indoor plants. Be aware that they do not totally take the place of fertilizers; especially for those plants that need the macronutrients N, P, and K.

A small amount of worm castings can be mixed with your seed starting soil.  They will provide your new seedlings with a safe, natural food for the new roots.  I have used worm castings in tropical plant soil and in outdoor mixed containers.  A little goes a long way.  As with other fertilizers, do not add more than directed.  More is not always better!

Another handy way to use worm castings is to steep the castings in water for a few hours and use that water to give your potted plants a boost.  Cheesecloth works well as a ‘teabag’.

Worm castings can be stored up to 6 months or longer, away from light and at a constant temperature.

1 comment

  • Very Interesting about Coir. I’ll be in to get some soon!

    Mary Lou Forrest

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