Straining your eyes? You can listen to this automated AI version of the article here:
Coco Coir vs Peat: Practical Facts You Need to Know
As somebody with green fingers, you're probably always on the lookout for ways to improve your yields and grow healthier plants. One of the most important factors in plant growth is the type of media bases you use and here we're going to discuss some practical facts on the coco coir vs peat debate.
There are many different types of media bases available on the market, but two of the most popular are coco coir and peat. Both have their own unique benefits and drawbacks, so how do you know which one is right for your garden?
To help you make an informed decision, we've put together a quick guide. Read on to learn more about these two media types and find out which one is best for your plants!
Coco coir is a type of soil made from coconut husks. It's an environmentally friendly alternative to peat, as it's a renewable resource that doesn't require mining or harvesting.
Being very absorbent, it makes a great medium for plants that need lots of water. However, this can also be a drawback, as coco coir can easily become waterlogged and compacted if you're not careful.
Coco coir is normally pre-treated by soaking it in a calcium buffering solution before you buy it. The calcium buffering solution leaches the salts out of the coir pith, then the coir bark can be used as a substrate for growing.
To use coco coir, you'll need to add some extra drainage material like perlite or vermiculite to your potting mix. This will help prevent your plants from becoming waterlogged.
Benefits of Using Coco Coir
- Coco coir has a Cation Exchange Capacity of 40-60.
- As a by-product of the coconut industry, it's a renewable resource.
- The pH usually runs between 6 – 6.7.
- Generally, it's cheaper than peat moss.
- Coco coir is not hydrophobic, so it's easier to rewet.
- It provides an optimal habitat for microorganisms.
- Coco coir has a water capacity ranging from 8x to 30x its own weight.
- With a high lignin content, coco coir breaks down slower than peat.
- Coco coir is completely free of pathogens, pests and weed seeds.
Drawbacks of Using Coco Coir
- Pesticides linked to honeybee deaths are being used to spray coco coir in tropical regions.
- Naso-bronchial allergies are prevalent among workers who harvest coco coir. This is due to the high amount of dust created.
- Coco coir needs to be hydrated before use.
- Depending on the batch and source of coco coir, the quality can vary.
- High salinity can be an issue, so the coco coir needs to be properly washed.
- Increased fossil fuel costs to import coco coir into New Zealand
- Negligible trace elements.
- Unless properly treated, magnesium or calcium deficiencies can occur because coco coir is high in potassium and sodium.
- There are no microorganisms in coco coir.
Peat “soils” are a highly productive growing medium, but they need drainage and cultivation to establish productive pastures and crops. However, this leads to irreversible shrinkage and oxidation (loss of carbon as carbon dioxide).
Peat can acidify its surroundings by taking up cations, such as potassium, magnesium, and calcium, and releasing hydrogen ions.
At the moment, Peat is sustainably harvested in New Zealand under quota. It is a locally mined resource and requires less fossil fuels to transport than coco. While the ideal situation is for peat bogs to be restored to pre-mining condition after they are mined, unfortunately, the jury is out on whether this is being achieved. Mining companies believe that this is a sustainable practice, however, this is a matter of conjecture, with an opposing view to the contrary.
As with coco coir, there are benefits and drawbacks for using peat.
Benefits of Using Peat Moss
- Peat has a Cation exchange capacity of 100-200.
- Peat can hold 10-20 times it's dry weight in water.
- Contains beneficial microorganisms and provides an excellent habitat for them.
- Peat is free of pathogens, weed seeds, and pests.
- Peat has a better C:N ratio.
- Contains sulfur, which provides proper terpene expression, and a variety of other beneficial elements.
- Peat is harvested in New Zealand, so this reduces the fossil fuel impact.
- Peat has an acidic pH, which means it can have highly alkaline amendments added such as Calcium, providing optimal ratios.
Drawbacks of Using Peat Moss
- Peat moss requires hydrating before use and should be kept moist, but not soggy.
- Peat moss can be quite dusty and cause respiratory problems if inhaled.
- Peat moss is slow to decompose, which can result in it becoming matted and difficult to work with over time.
- It is hydrophobic, which means that if it dries out, it will initially repeal water when it comes into contact with it.
- Because peat moss depletes peat bogs, they must be manually re-built. In addition, they must also be harvested sustainably.
In a Nutshell
So, deciding which growing media is the best is clearly not a one-size-fits-all decision and we all have our preferences.
One school of thought contends that sphagnum peat moss is superior because the pH is acidic, meaning you can add highly alkaline amendments such as biochar or calciumin the form of oyster shell, or ag lime. Peat moss's existing microbiology is also considered an advantage.
Further, there have been a few examples of quality control issues with coco coir, with a huge variance between batches containing high salinity from the same manufacturer.
No matter what you choose, you'll probably want to add perlite or pumice for aeration and add nutrients in order to improve fertility such as worm castings or compost. Adding a rate of 15-50% of the total media to increase biological diversity and organic matter is recommended.
The opinions on coco coir vs peat are varied, but there are some clear advantages and disadvantages to each, and we hope we've been able to provide some food for thought and points to consider.