Coco Coir vs Peat Moss: Differences + Which to Use

Coco coir and peat moss are both popular products used in container gardening and hydroponic growing. They are all processed and sold as potting media, soil amendment, or mulch. Let’s compare coco coir and peat moss in terms of their characteristics, benefits, sustainability, and effectiveness. 

Peat moss is harvested from bogs containing sphagnum moss and other organic materials that have decomposed over thousands of years. Peat moss is a water retainer but well aerated thus commonly used in improving soil drainage. It is easy to find in garden stores or nurseries in the US.

However, peat moss is a non-renewable resource that takes longer to replenish and its harvesting can damage the environment by causing green gas emissions and habitat destruction. Additionally, it can be more acidic than most garden plants prefer. This has made coco coir a popular alternative to peat moss.

Coco coir is typically a byproduct of coconut production. The fibrous material found in the husks of coconut is processed into a peat-like substance. It has excellent moisture retention, neutral pH, and great aeration. Coco coir is a renewable resource, and its production is less harmful to the environment.

Here’s a table summarizing the key differences between coco coir and peat moss:

Coco Coir	Peat Moss
It is derived from coconut husks.	It is derived from decomposed sphagnum moss in the bogs.
Has excellent moisture retention and drainage	Has relatively higher water-holding capacity and may become compacted if not amended.
Near-neutral pH (5.8-6.8).	Acidic (p H of 3.0 – 4.0).
More environmentally friendly, since it’s a waste product from coconut production.	Harvesting can impact the environment, through greenhouse gas emissions and potential habitat destruction.
Has strong natural antifungal properties.	Relatively disease-free, but potential for harboring pathogens.
Can be reused with proper sterilization and preparation.	Difficult to reuse due to decomposition and potential contamination.
It is easier to re-wet when it dries out.	Once dry, is very hard to rewet.
More expensive due to shipping costs	Relatively inexpensive in the USA.

Coco coir vs peat moss 

Here is a detailed comparison of peat moss and coco coir.

Source and Sustainability

Coco coir is derived from the fibrous husk of coconuts. It is a renewable resource as coconuts are readily available and harvested regularly for food, oil, and other fiber products. However, coco coir is hard to find in bulk in the US as most of it has to be shipped from overseas.

Peat moss is harvested from decomposed sphagnum moss found in peat bogs. It is considered a non-renewable resource that also takes hundreds or thousands of years to form. Peat moss is largely produced in Canada and shipped to the US and other parts of the world.

Water retention and drainage

Coco coir has excellent moisture retention capabilities than even regular soil. Simultaneously, it provides good drainage. This means plants will be well hydrated and roots aerated, which helps in reducing the chances of root rot. The product also re-wets easily when it dries out.

Peat moss naturally holds water like a sponge and can cause root rot problems when overwatered. Once dry, it becomes difficult to re-wet and this can be a problem for many plants like cacti which are watered only when the soil feels dry.

pH and nutrient content

Coco coir has a near-neutral pH, which is beneficial for a wide range of plants. However, it has no nutrient of its own content and may require to be supplemented with fertilizers. On the other hand, peat moss is acidic and only suitable for acid-loving plants. It also has no nutrients and may require additional fertilizers.

Environmental considerations

Coco coir is considered to be more environmentally friendly as it is a byproduct of coconut production. It is typically a waste material that would otherwise be discarded. More so, coco coir can be reused multiple times when treated or sterilized, unlike peat moss which decomposes over time.

Harvesting peat moss degrades peat bogs, which are important ecosystems that also act as carbon sinks. Its extraction releases carbon back into the atmosphere something which contributes to global warming.

Experts note that bogs represent 5% of the earth’s surface and yet they contain more carbon than all of the planet’s forests combined.

Disease resistance

Coco coir has strong natural antifungal properties, which can help prevent certain plant diseases. Peat moss, on the other hand, is relatively disease-free but can sometimes harbor fungal spores or other pathogens harmful to the plants.

Which is better?

The choice between coco coir and peat moss often comes down to the specific needs of your plants, environmental concerns, and personal preferences.

If you are looking for a sustainable option for a wide variety of plants, then coco coir may be a good choice. If you are on a budget, then peat moss may be a better option.

According to Oregon State University, Coir has proven to be better than peat since it holds moisture well, wets more easily, drains well, decomposes more slowly, and withstands compression.

Coco coir pros

• Has neutral pH, which is better for many plants.
• It is a byproduct of coconut processing thus less waste.
• Coco coir is a renewable resource.
• Can be compacted for shipping and storage.
• Can be rehydrated when it dries out.
• Retails moisture and aerates soil well.
• Helps solve a waste disposal problem in landfills.

Coco cair cons

• Can be expensive and harder to find in bulk.
• Generally shipped from overseas which increases its cost.
• Does not have its own nutrients and needs extra fertilizer.
• Used to have high salt content, but the current processing method has resolved the issue.

Peat moss pros

• Easy to find in many gardening stores.
• It loosens compacted soils and enhances aeration.
• Promotes moisture-holding capability of sandy soils.

Peat moss cons

• It is more acidic than most garden plants prefer 
• Once dry, is very hard to re-wet (hydrophobic)
• Harvesting causes massive damage to the environment and local habitats.

Can I mix coco coir and peat moss?

Yes, you can mix coco coir and peat moss when making your own potting mix. Together they will boost the water-retention capacity of the soil, improve drainage and boost aeration.

When mixing the two, it is important to use the correct proportions. A good rule of thumb is to use 2 parts coco coir to 1 part peat moss. You also need to pasteurize the mixture before you use it. Heat the mixture in an oven or microwave to kill harmful bacteria, fungi, and other pathogens.

Final Thought

Overall, both coco coir and peat moss have their advantages and considerations. Coco coir is more sustainable, has better drainage, and is easier to rehydrate. Peat moss has higher water retention, is suitable for acid-loving plants, and is widely available.

References

Soilless Growing Mediums, by Dharti Thakulla, Bruce Dunn, Bizhen Hu; Oklahoma State University.

Homemade Potting Media, by Jim Sellmer, Ph.D. and Kathy Kelley, Ph.D.; The Pennsylvania State University

How To Change Your Soil’s pH, by Joe Hannan; Iowa State University.