Peat Moss: What it is and How To Use It In Your Garden

Surely you have seen big bags of peat moss in garden centers? Used as a growing medium in pots, decorative and vegetable gardens, peat moss has become very popular thanks to its excellent qualities. 

Peat moss can be used as a component of potting soil or to make compost, it is fully organic and it can improve your soil.

But what is peat moss, where does it come from, and is it really sustainable?

Peat moss is a fully natural and organic fibrous growing medium coming from sphagnum, a group of plants that grow in cold marshes; it has excellent properties in potting soil, as a soil improvement ingredient and for seedlings. However, it is not sustainable and it has a huge environmental impact,

So, if you want to use peat moss in your garden, there are a few factors to take into consideration.

Read to learn more about peat moss, what it is, how it forms, how it gets into garden centers, how you can use it, and also why you should be thinking twice before buying it.

5 Best Ways To Put Peat Moss To Use In Your Garden

Peat moss has a fine and light texture, it holds on to water and lasts for a long time; this is why it has become useful in gardens and as a potting mix for houseplants.

Over the years, gardeners have found five main ways of using this natural resource we call peat moss:

  • Peat moss is used in potting soil, usually mixed with other media.
  • Peat moss is used when transplanting plants; when plants change soil, peat moss helps them adapt to the new soil composition.
  • Peat moss is used to improve soil; in fact, added to clay or sandy soil in particular, it can make it more suitable to farming and gardening. We will see how.
  • Peat moss is used grow healthy lawns; its water and air retention qualities make it ideal to add to your lawn soil.
  • Peat moss is used in composting; as it is rich in carbon, you can use as an ingredient of your compost heap.

What Is peat Moss?

what is peat moss

Peat moss is fully natural; it is a fully organic growing medium which comes from bogs, especially from cold places like Russia, Canada, Scotland etc.

There is no transformation process, no Human hand, no advanced technology involved in making it.

It is simply quarried. Sometimes, it it also gets compacted, and this is why you can find it either as solid “bricks” or as loose fibrous matter. Once it has been dug out of the ground, it is bagged and sent straight to distribution centers.

The quarrying is done without having to dig deep, as peat moss comes from just under the surface.

Where Does Peat Moss Come from?

Peat moss comes to your flower pot or garden from wetlands, or bogs.

It is not decomposed material, and this is because the water on the surface of the bog does not allow oxygen and air to filter underground. 

So, the fibers of the sphagnum moss remains almost intact.

The weight of the water and living moss on top, however, presses it down, forming a dense mesh of fibers that is what we call peat moss.

On average, peat moss only grows by 0.02 inches (which is only 0.5 millimeters) every year. It is therefore, a very, very slow process.

What Is Peat Moss Made of?

Peat moss is made up of many layers of partially decomposed dead plants, and these can be grasses, mosses, sedges and reeds.

Thus, it is not fully decomposed matter. This is very important, because it preserves the porosity of the fibers that these plants have.

This means that it can soak up water and even have pockets of air, which allow roots to breathe.

In chemical terms, peat moss has a ratio of carbon : nitrogen of 58:1, which means that there are 58 grams of carbon for each gram of nitrogen in peat moss.

This makes it an excellent source of carbon in compost, potting soil, or mixed in with other types of soil.

What’s the Difference Between Sphagnum Moss and Peat Moss?

Don’t confuse peat moss (also sphagnum peat moss) with sphagnum moss. They come from the same plants, any of the Sphagnopsida class but they are not the exact same thing. Peat moss is what ends up under the water of these plants, while sphagnum moss is collected from the still living floating parts of the plant.

Their uses are different too: peat moss is uses as potting soil, or to improve soil and similar uses, while sphagnum moss is used as ground cover and also to weave baskets and miniature furniture, in fact you will find it also in craft and hardware stores as well as garden centers. Finally, peat moss is slightly acidic, while sphagnum moss is neuter.

So, both come from sphagnum but peat moss is used for soil improvement, because of its ability to change the texture of soil and water retention properties and because its low pH can be used to correct the soil’s acidity.

On the other hand, sphagnum moss is only used as mulch or for decorative purposes in gardening.

The History of Peat Moss

The history of peat moss is very old indeed; in fact, the brown fibers you find your local nursery are usually 10,000 to 12,000 years old.

They used to be plants, mostly one of or more of the 380 species of Sphagnopsida.

Living in bog lands and marshes in continental climates, when they die, they sink under the water.

There, they lose decomposable organic matter and retain the fiber, which is hard to destroy in the absence of oxygen.

But from there to the soil in your pot, the journey is not that short. Peat has been known and used as fossil fuel for centuries if not millennia, but it was only after the Second World War, with the advent of “industrial farming” that peat moss found its way into the agricultural market.

It was first received as the solution to many problems, and in fact it does have some great properties.

But later one, as environmentalism and “green consciousness” started to spread, from the 80s onwards, so came worries about depleting the world’s natural resources.

In recent years, we have learned that peat bogs are key to the survival of the planet, and its use in gardening and agriculture is now frowned upon by most gardeners with an environmental sensibility.

What Are the Benefits of Peat Moss?

Benefits of Peat Moss

In gardening, the properties of the soil or growing medium you use are a very important factor to consider.

Peat moss has some very important qualities that have made it a favorite with farmers, gardeners, growers and amateurs all over the world.

  • Peat moss holds onto nutrients; fertilizing or feeding the soil is a waste of time unless it can hold on to the nutrients. Fibers absorb them and then release them slowly to the roots of your plants.
  • Peat moss holds on to water; again because it is fibrous organic matter, it soaks with water and then releases it slowly. In fact, it can hold as much as 20 times of its weight in water. This quality, as well as its ability to retain nutrients, is helpful if your soil is sandy, which means that it does not hold on to moisture and nutrients.
  • Peat moss can hold on to air; roots need to breathe as well as feed and drink and in the pores and spaces within the fibers of peat moss, air can find a good place to hide.
  • Peat moss has a slightly acidic pH; this makes it a good acidity corrector, especially with plants that cannot stand and alkaline soil.
  • Peat moss helps break the ground; putting organic matter in the soil, and in all cases varying the texture of the soil, allows for better aeration, feeding and humidity retention. Because the fibers of peat moss beak down slowly, it has become popular with gardeners who want to correct the texture of clay soil in particular.
  • Peat moss is sterile; because it has formed in an anaerobic environment and many bacteria need oxygen to live, it is free from pathogens that can harm the roots of your plants.
  • Peat moss has long decomposition times; the fibers peat moss is made of decompose slowly, and because they have been “treated” underwater for a very, long time, they are even more difficult to break down. This means that it has a very long life in the ground.
  • Peat moss is fully organic: by now you know that it is sourced from bogs and it is fully natural. However, the quarrying and transportation does burn a lot of fossil fuels, so, if it is produced organically, it is not harvested and delivered organically.

Before we move on, there is an important point; peat moss is very good at retaining water, but much less so with air.

This explains why it is almost never used on its own. But more to this in the next section…

What Are the Downsides of Peat Moss?

Peat moss is popular, sought after and also useful as a growing medium or soil corrector, but it is by no means perfect. In fact…

  • Peat moss is not sustainable; it takes Nature 500 years to make 10 inches of peat moss. This issue has become central in the gardening world, and especially in the organic community and among gardeners who are aware of sustainability. Its quarrying is now strictly limited and regulated in many countries, like in Canada, in fact. Most gardeners have that feeling of remorse when using it nowadays.
  • Peat moss is expensive; it far exceeds the price of comparable mediums, like coconut coir. In fact, you are more likely to find it mixed in with other mediums already.
  • Peat moss tends to compact over time; under the pressure of water, peat moss becomes compact and thick, which means that it loses its aeration and absorption properties. This is remedied by mixing it with other media, especially perlite.
  • Peat moss is poor in nutrients; it is not decomposing matter, which means that while you can use it to change the texture and properties of your soil, it is not the best choice if you have organic regeneration in mind. For example, earthworms are not attracted to peat moss, nor are many of the microorganisms that turn the soiled fertile.
  • The acidity of peat moss does not suit all plants; most plants, as you know, love neutral to alkaline soil, and peat moss is acidic.

The Environmental Impact of Peat Moss

We need to talk about the environmental issues surrounding the quarrying of peat moss before we move on.

All conscientious gardeners should be very aware of these, and if you are not new to this growing medium, for sure you will know that there has been a strong argument against using it on environmental grounds.

Every inch of peat moss takes decades to form. This is a major problem, but there is more…

Peat bogs cover 2% of the land in the world, but it stores up to 10% of all the carbon in the world. This means that these bogs are central to eliminating carbon dioxide from the atmosphere and we all know what it means in terms of climate change.

Finally, excessive quarrying means that peat moss is quickly running out.

Now you know all this, I am sure you will think twice before buying it.

How To Use Peat Moss In The Garden

Use Peat Moss

Peat moss became very popular in pots and flower beds and vegetable garden with gardeners in the past decades, till they became aware of the environmental issues.

Let’s assume you have some to recycle and you want to use it, then, how can you go about it?

We have seen that there are five main uses of peat moss in gardening; now we will see each in turn.

1: Peat Moss As Potting Soil

Peat Moss as Potting Soil

Peat moss is very common in potting soil mixes. In this respect, it has some important qualities:

  • It retains moisture.
  • It releases nutrients slowly after you feed your plants.
  • It improves the texture of the potting soil.
  • It does not have weed seeds.
  • It is sterile.
  • It lasts for years (about a decade).
  • It is good for acidophilic plants, like azalea, camellia, raspberries etc., plants that like acidic soil.

Peat moss is usually mixed in with other media, like perlite, for example, because perlite holds onto air, thus improving the aeration of the mix. Less frequently, vermiculite is used, in case the plant likes high levels of humidity.

Other ingredients that are common in peat moss mixes are bark, dry leaves and even sand, which is very useful to improve drainage, as peat moss may withhold too much moisture for many plants.Some gardeners use it on its own, especially for seedlings, because it has no weed seeds.

2: Pet Moss For Plant Transplants

When you transplant your flowers, vegetables or other plants, the roots will need a welcoming environment to settle in.

This is something all gardeners are very aware of. If the soil is too thick or hard, for example, especially plants that like friable and acidic soil will see their radical growth restrained.

So, especially with shrubs and berries, but also with rhododendrons and similar plants, gardeners have taken to adding peat moss to the soil. This has some advantages:

  • Peat moss breaks down the consistency and texture of the soil, especially if it is clay.
  • Peat moss corrects the acidity of the soil.
  • Peat moss slows down the nutrient release after you fertilize.
  • Peat moss keeps the humidity high, which is essential when plants have a new home.
  • Peat moss provides nooks and crannies where new, tender roots can grow.

3: Peat Moss To Improve Soil

Peat Moss to Improve Soil

Trust me, I don’t envy gardeners who have to deal with clay or sandy soil. Clay has a very hard texture, thick and heavy, sand is the exact opposite, but it holds on to nigh on no water and nutrients.

Peat moss has exactly those qualities that clay and sandy soil lack:

  • Peat moss breaks the texture of clay, which is too compact. This makes drainage better and it makes the soil easier to work.
  • Peat moss adds texture to sandy soil, which lacks it. This makes it hang together better, with positive consequences on nutrient and water retention.
  • Peat moss holds on to nutrients and water; both clay and sand have very bad patterns of water and nutrient retention and release. Clay retains a lot of water, and peat moss can provide drainage, while sand holds no water at all, and peat moss can do it instead.
  • Peat moss corrects the acidity of clay, which is very alkaline, actually, too alkaline for many plants…

In these cases too, peat moss is added to the soil, you will not totally replace the soil you have with it.

Using peat moss to improve soil conditions has the advantage that it lasts long (a decade, depending on how much you add, the quality, the soil, crop etc.) On the other hand, peat is mainly corrective and not regenerative. The best way to change your soil quality permanently is through regenerative techniques.

4: Peat Moss For A Healthy Lawn

If you have a lawn, you will know how hard it is to keep it in good shape, healthy and green.

Much of the success depends on the quality of the soil, especially the top soil, which needs to be well aerated, retain moisture but never get waterlogged and to have a good structure and texture, not too compact and not too loose.

Peat moss has many qualities that can help you have the best lawn in the neighborhood:

  • Peat moss retains moisture.
  • Peat moss retains nutrients.
  • Peat moss allows the roots of the grass to grow because it improves the texture of the top soil.

There are two ways to add peat moss to your lawn:

  • To improve the quality of the top soil of your lawn you can add peat moss to the soil itself before seeding or planting your lawn.
  • Alternatively, if you already have a grown lawn, you can sprinkle peat moss on the surface, and the rain will slowly bring it into the ground.

5: Peat Moss For Composting

Using peat moss to make compost may not be the best use of your money, but it is one of the ways of using it.

Let’s put it like this: if you don’t know what to do with your peat moss, you may as well use it for your compost.

As we said, peat moss is very rich in carbon; it also has a texture that allows gaps and pockets where small creatures that take part in the decomposition process can find shelter.

Compost usually wants a ratio of carbon : nitrogen of 30:1, and peat moss has almost twice that. So, it can be used to increase the carbon in your compost.

There are a few ways to use peat moss in compost:

  • You can use peat moss as a carbon base; in this case, spread a layer of peat moss and add nitrogen rich matter on top, then proceed with the other layers of your compost heap.
  • You can mix peat moss into the compost heap.
  • You can add peat moss to other carbon rich ingredients, like dry leaves, cardboard etc.
  • You can correct the carbon to nitrogen ratio of your compost heap. When your compost heap smells a lot, it means that it has too much nitrogen. Peat moss has a fine texture and it is easy to mix it in to correct this.
  • You can add peat moss on top of your compost heap and mix it in; this can be done as the compost starts forming, and the base is being decomposed.

Organic Alternatives To Peat Moss

The environmental issue and the cost can put many gardeners off using peat moss. Fortunately, there are alternatives for all its roles.

Below, we take a look at some of the stainable peat moss substitutes you can use instead:

1: Compost

Compost

You can use compost as peat moss substitutes to change the soil’s fertility and acidity. With clay soil, compost will also improve its drainage properties, breaking down the clay, but the effect is much improved if used in conjunction with sand.

Compost is cheaper than peat moss and fully sustainable, and you can easily make your own. On the other hand, compost will not last as long as peat moss, and you will have to add compost regularly.

Finally, compost will compact faster and more easily than peat moss, but to have a comparable effect, you can add sand, shells and egg shells to the soil to improve its texture.

2: Perlite

Perlite

Perlite is a volcanic rock rich in pores, and it is good for water retention and air retention. It is often used in conjunction with peat moss, as we said, because it has better air retention properties than peat.

Perlite will last forever as well, which is an added plus. It has the ability of providing good moisture and aeration while at the same time breaking up soil texture when it is too compact. 

Perlite is organic as well, though, of course, the quarrying uses fossil fuel. It is also inert, like peat moss, which means that it can hold on to nutrients for long, but it does not provide any itself. It is readily available as well, which is why it is a favorite with gardeners all over the world.

3: Vermiculite

Vermiculite

Vermiculite is a mineral used as organic peat moss substitutes in gardening which, when heated, expands, forming pores and pockets where air and water can be stored and released slowly.

It is better than perlite at holding water, but not so good at preserving air. In this, its properties are more similar to those of peat moss.

Vermiculite too is inert and it will last forever, so, it is an excellent way of improving both the texture and properties of the soil permanently.

While the rock itself is natural, the heat needed to expand it in furnaces does pose an environmental problem.

4: Sand

Sand

Sand is excellent suitable alternatives to peat moss to break down clay soil and improve the texture, aeration and drainage of soil. It too is inert, so, it will not affect your soil pH and nutrients of your soil.

What is more, sand is very easy to add to soil; you will, in most cases, only need to scatter it on top of the land you wish to improve, and it will soon seep into the ground.

If your soil is rich in clay, sand and organic matter (like dry leaves, for example) will greatly improve its texture, aeration and drainage.

Keeping in mind that sand is very cheap, easily available and does not have a major impact on the environment, it can be a much better option than peat in some of its functions.

5: Coconut Coir

Coconut Coir

Coconut coir is the fiber obtained from the outer husk of coconut and it has become a great favorite with organic gardeners as suitable alternatives to peat moss. It is cheap, fully renewable, readily available and it can be used both for soil improvement and as a growing medium.

It is inert too, and it has good aeration and water retention properties. In terms of texture, it is not dissimilar to peat moss, but unlike it, it is just a byproduct of coconut farming, and it has no impact whatsoever on the environment.

If your problem is soil texture, aeration and water or nutrient retention, the coconut coir is by far the best choice you have.

6: Organic Matter

Organic Matter

Partly decomposed organic matter, like dead leaves, can be used as alternatives to peat moss if your soil is sandy, to improve water retention and even to give nutrients to your soil and change its texture.

Sand will just allow water and nutrients to run off freely, but if you add organic matter, this will soak up the moisture and release it slowly.

It will also, in the long run, fertilize your soil, which is a major issue with sandy soil in many cases.

Regenerating The Soil

Soil regeneration is part of one of the major revolutions in gardening in the last century. It starts from the idea of restoring a balanced ecosystem, where the planting (water management and even landscaping) improves the soil.

This is not just a permanent solution, but an incremental one: it will get better and better year on year, giving you healthier and healthier soil and higher and higher yields as time goes by.

So, if peat moss is used for soil improvement, it does not offer a permanent solution.

Using it, or even better its alternatives can be a temporary solution, but if you really love your land, looking into regenerative agriculture is stepping into the future, of your land as well as of gardening.

Peat Moss: Does It Have a Future?

We have covered a lot of ground in this article on peat moss. It is an excellent ingredient in potting soil and in growing media, as you can see.

It became very popular a few decades ago, and it has since become widespread and much used by gardeners.

Good in potting soil, as a growing medium, to correct soil, to grow a good looking lawn and even in compost, it was at first hailed as the answer to many problems… Until… Well, until gardeners realized that it is a finite resource and that its commercial fortune went hand in hand with its disappearance.

We then found out that it is key to combatting climate change, so, now, most gardeners regard using it as an actual environmental crime.

Luckily enough, while the fortune of peat moss started fading, resourceful gardeners have found alternatives for all its purposes that are cheaper, renewable and even more easily available.

So, if you ask me whether peat moss has a future, I would say, “Yes, it does, but maybe not in our gardens, but in the natural peat bogs where it can do more good to your plants than inside your potting soil.”

Updated on by Amber Noyes

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