Using peat-free products in the home and garden is one of the simplest yet most effective ways that people can make a positive environmental impact and reduce their carbon footprint. For most uses in the garden, for example, pots, growbags, hanging baskets, digging into or tidying up flowerbeds, peat-free alternatives are just as good as peat-based compost, and they don’t lead to the loss of our valuable peat bogs.
After hundreds of years of use as a fuel source, peat moss gained new popularity with savvy gardeners in the 1940s. It offers tons of horticultural benefits – with one huge drawback: it takes so long to form that it’s considered a non-renewable resource.
And many gardeners may not realise the damage that peat extraction causes to the environment – or know that the compost they’re buying even contains peat. Given the current ecological trends, many countries are banning the use of peat in gardening.
So, what can we use to replace the tried, tested and true peat moss?
Why is peat moss such a good addition to the garden?
Peat is made up of dead and partially decomposed mosses and plants that have slowly built up under cool and wet conditions. The creation of Britain’s peat bogs actually removed 5.5 billion tons of carbon dioxide from the atmosphere and locked it into the ground.
Peat moss occurs when this process happens in areas where there is plenty of sphagnum moss. It’s incredibly spongy and can retain up to 25 times its weight in water – yet it still drains freely. The excess water quickly moves through the peat and drains out.
Peat moss is easy and clean to work with. It’s also acidic – with a pH between 3.5 and 6 – making it a good choice of growing media for acid-loving container plants. You can use it to lower the pH of alkaline soil.
Peat moss weighs less than topsoil. After harvesting and drying, peat moss weighs approximately 25 pounds per cubic foot while a similar volume of topsoil weighs about 40 pounds. Furthermore, the dried moss is springy and resists compaction, keeping plenty of space around the roots.
One of the best things about peat moss is that it doesn’t contain bacteria, fungi, weed seeds, or harmful chemicals like other growing media might. This makes it a fantastic product for starting seedlings.
Some drawbacks of peat moss
In some applications, the slight acidity of peat moss can be a problem. Not all plants thrive in acidic soil. Also, because the bogs in which peat moss form are nutrient-poor, peat moss is typically low in nutrients too.
But the biggest drawback is that peat moss forms incredibly slowly compared to other materials. Because peat forms a rate of only 0.04 inches per year, a 10-metre deep peat bed can take nearly 10,000 years to form, but – because peat extractors remove up to 9 inches per harvest, that bed can be cleared in fewer than 50 years.
The peat moss harvesting process is more labor-intensive than others, making it more expensive to purchase than some other alternatives.
Why should I consider peat moss alternatives?
In its natural environment, peat moss purifies water, prevents flooding, and absorbs carbon dioxide. In fact, peatlands store a third of the world’s soil carbon. But sadly, their harvesting and use releases carbon dioxide (the major greenhouse gas driving climate change) into the environment.
Harvesting peat bogs also destroys unique ecosystems that support various species of insects, birds, and plants.
What is a good alternative to peat moss?
Compost is a good substitute for peat moss because it contains many beneficial microorganisms. It also improves drainage, attracts earthworms, and provides nutritional value to the soil. There are no major drawbacks to using compost as a substitute for peat moss, so long as you remember to replenish compost regularly.
You can use either leaf mold or manure compost which is at least one or two months into its development. Composting your yard waste, food waste, or animal waste means less going into landfills – helping to decrease greenhouse gas emissions.
Another advantage to using compost is that making your own compost cost little to nothing.
And yet, there are downsides to using compost as well:
- It’s heavy and can lead to soil compaction if used alone (aim for a mix of 1/3 compost in your soil)
- As it breaks down, its nutritional values decreases so it must be replenished every year or two
- Creating your own compost can be time-consuming and labor-intensive
- It can be a source of weed seeds, diseases, or even hormones or antibiotics from animals
- The smell – especially of manure compost – is quite distinct and off-putting
Wood-based materials such as wood fiber, sawdust or composted offer many benefits, particularly when they’re made from byproducts of locally sourced wood. By adding organic matter to the soil or potting mix, you allow for better air and water movement.
Furthermore, if you have a lot of trees on your property, you can easily create your own wood mulch. Even if you choose to buy commercial wood products, they are fairly inexpensive. Often sourced from waste wood at sawmills or provided from landscape companies, wood products a highly renewable resource. Many municipalities offer free wood chips to their residents.
Remember, though that wood-based products have high carbon levels. So, when you add them to your soil, they will tie up usable nitrogen as soil microorganisms try to break the wood down. This means that you’ll need to add extra nitrogen fertilizer to the soil to maintain the proper ratio of carbon and nitrogen for plant growth.
A wood-based amendment may also contain chemicals if the scraps are from treated wood; or glue, if they’re made of plywood was turned into sawdust.
Coconut coir, also known as coco peat, is one of the best alternatives to peat moss. Harvested from mature coconuts, the type of coir typically used in potting soil is very slow to break down – meaning that is doesn’t need to be replenished often.
Coconut coir can be used just like peat moss. With a pH level of 6.0, which is close to perfect for most garden plants, coir can also hold up to 10 times its weight in water. It allows for good drainage and root aeration too. The natural antifungal properties of coir can reduce the growth of fungus while promoting the growth of beneficial bacteria around the roots.
The are some drawbacks to coir though. It is low in nutrients such as nitrogen, phosphorus, and potassium so you’ll need to fertilize regularly to keep your plants well-fed. And while the high porosity of coir allows for excellent water and air movement through the roots, it doesn’t typically have enough structural stability to really hold your plants upright. You may need to stake them or use another type of support structure.
If the coconut husks are soaked with saltwater to soften them, coir can contain a large amount of salt which – if not flushed out properly – can damage your plants. And some lower quality products might have chemicals applied to them to prevent bacterial growth. Sadly, this can also eliminate beneficial organisms – and means that you must remove all the chemicals before use.
So, what can you use instead of peat moss? The products listed above come from more renewable sources, are typically less expensive than peat moss, and would all make a great addition to your garden. So which is the best for you and your plants?