Peat moss is a timeless favorite for farmers and gardeners alike.
Now you are probably wondering what it is. How is it different than sphagnum moss?
In this post, I’m going to help you to find out everything you ever wanted to know about plus how to use peat moss in your hydroponic or soil garden!
Any gardener knows that the secret to gardening success is your growing medium.
Whether you are a conventional gardener or a hydroponic grower, the soil or growing medium needs to provide the plant root systems with:
- good aeration
- good drainage
- retains sufficient moisture in the soil
- and has the ability to absorb nutrients
What is peat moss?
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Peat moss is probably a word you have heard before, but do you actually know what it is and the role it plays in determining the quality of good compost?
Quite honestly, the first time I used it I thought it was awful stuff.
I didn’t know you had to actually soak it first and then use your hands to mulch it up and squeeze out the moisture before you got the lovely spongy, workable end product.
Now I can’t live without it!
Traditionally, peat moss has always played a vital role in improving the soil.
It is a major component in the growing mediums formulated for seedlings, right up to the compost used for transplanting trees and shrubs.
It has many practical applications and benefits as well as a few drawbacks.
Difference between sphagnum moss and peat moss?
Peat moss is also known as Sphagnum peat moss.
The difference is simple. Peat moss is just dead Sphagnum moss.
This primitive plant species known as Sphagnum moss is part of the group of plants known as Bryophytes.
These plants bear no seeds or flowers, producing spores instead.
They thrive in moist, shady environments, and when the mosses decompose these wetlands turn into peat bogs.
Wet, cold, oxygen-poor conditions mean that the presence of bacteria is reduced and plant growth is greater than the rate of decomposition.
Over time the dead vegetation turns into peat moss.
Both the living sphagnum and the dead peat mosses are harvested.
First, the living moss is harvested, and then the dead.
Sphagnum moss is used differently from sphagnum peat moss as they are very different in appearance and function.
Sphagnum moss is at the top of the bog, and peat moss is the decomposed product deeper down.
Different grades of peat moss are graded using the Von Post Scale for Decomposition, where H2 is the light, spongy formation, also known as blonde, and H8 is the dark, decomposed peat that feels like putty.
The scale starts at H1 and goes up to H10.
The largest peat bogs are found in Russia with Canada coming in second.
Countries like Finland, Sweden, Ireland, and Germany also have ideal climatic conditions for bogs to develop.
Why use peat moss in gardening?
Peat moss is first and foremost a soil conditioner, or soil amendment.
Soil conditioners repair damaged soil by loosening compacted soil to improve aeration and increase the water-holding capacity.
By helping to bond nutrients and water together to help the roots absorb both moisture and food.
The greatest demand for peat moss comes from the horticultural industry, but it is used by farmers, landscapers, and gardeners alike. It also has important uses in other industries.
Not only is it a porous, fibrous material, but it also bears traces of vitamins, polyphenols, and humic acid.
It has a slightly acid pH and an above-average moisture-holding capacity.
But the nutrients in it are by no means sufficient enough to call peat moss a fertilizer.
It is, however, a disease suppressant and free of weed seeds.
As a soil conditioner and amendment to growing mediums it has many benefits:
Benefits of peat moss in gardening
There are numerous reasons why using peat moss in gardening is beneficial. Below are just a few reasons why you should use peat moss in gardening:
- Peat moss pH is slightly acidic
- Loosens hard compacted Clay soils
- Retains water well
- Used as a soil amendment
- Sterile growing medium
- Peat moss is organic
- Increases nutrients in the soil
- Slows down decomposition in composting
- Peat moss is readily available
Peat moss pH is slightly acidic
This increases the soil’s buffering capacity, preventing the leaching of fertilizer nutrients. It also means it is ideal for a wide range of acid-loving plants.
Loosens hard compacted clay soils
Peat moss loosens hard compacted soils, improving their porosity, while still keeping its absorbency. Due to the slow decomposition rate, one application can last a long time.
Retains water well
Peat moss increases the moisture-holding capacity in sandy soils, conditioning them, increasing the absorption rate, and raising the bioavailability of nutrients.
Used as a soil amendment
Peat moss can be used as a soil amendment and can be added to compost and potting mixes. Because it acts as a soil amendment, it is an important additive to any custom compost or potting mix.
A compost/potting soil with peat moss will have a longer lifespan than one just using plain bark chips, for example
Pro tip: On its own, peat moss is just crumbly or powdery dry matter, but once soaked and allowed to absorb water, it becomes a spongy, workable medium. So make sure to pre-soak before adding to your mix. Pre-mixed composts or other growing media already containing peat moss will eventually rehydrate.
Sterile growing medium
Peat moss is weed and pathogen-free.
It has disease-suppressing qualities against certain root-rot pathogens.
Peat moss is ideal as a component in hydroponic growing mediums or as a soil amendment to growing mixes like potting soil.
Peat moss is organic
Used for propagating seedlings both in organic farming and hydroponics.
Pro tip: To make sure you buy peat moss suited to your specific needs, check to see if it is pure and organic or if it has been supplemented with other ingredients or fertilizer, which could kill sensitive carnivorous plants.
Increases nutrients in the soil
Known as cation exchange capacity (CEC), this means nutrients in the soil are unlocked and become available to plants through the roots.
Slows down decomposition in compost
What makes peat moss unique? is that it has a slower rate of decomposition due to its ability to decompose without oxygen (anaerobic).
It won’t rot in wet conditions making it great for adding to compost heaps where you want to lock nutrients in and slow down decomposition.
Peat moss is readily available
All these characteristics aid and improve nutrient absorption, which in turn helps a plant to grow strong and healthy and produce good-quality flowers and fruit.
In today’s world where our soils have been depleted through overuse and erosion, where some soils are just not fertile and friable by nature.
Many people live in urban environments where container gardening has to be practiced.
The use of added compost and substrates like peat moss is essential for growing plants to their full potential.
All these characteristics aid and improve nutrient absorption, which in turn helps a plant to grow strong and healthy and produce good-quality flowers and fruit.
Disadvantages of peat moss for gardening
Peat moss is considered a great soil additive that can aid with drainage and aeration.
However, there are some drawbacks to utilizing peat moss in your garden. Peat moss is a finite resource. It takes hundreds of years to form again after being removed from the bog.
As a result, peat moss is becoming increasingly scarce and expensive. Plus, the process of obtaining and processing peat moss is very environmentally taxing.
Not Environmental Friendly
Peat moss is harvested from peat bogs.
Peatlands have their own ecosystems and are home to many orchids, shrubs, carnivorous plants, and mosses that can only be found there.
They play a huge part in reducing greenhouse gases and are rich in carbon. Many birds nest here and mammals and insects hunt and feed in these peat bogs.
Considered a nonrenewable resource
This is a subject of great controversy.
Most of the peat moss used in gardening comes from Canada. Most of the peat moss used as fuel comes from other countries.
Because of the sensitive subject of whether or not it is ecologically viable to support the peat moss industry.
I did some thorough research and I have to say, in my humble opinion, I see a lot of effort, money, and research have been made, not only to manage it but also to rehabilitate it.
Pro tip: When buying peat moss, choose a trustworthy, well-established company. A company that implements sound harvesting practices and has programs and initiatives in place that give back to the earth and the community.
Not the cheapest choice
Sourcing a brand that is affordable and of a good standard is paramount. Because there are so many brands out there, often in the past.
I have found I’ve paid too much for too little or the quality is substandard.
The trick is to find a brand that is reasonably priced and offers a consistently good grade of peat.
Alternatives to Peat Moss for Gardening
If you are still not convinced that peat moss is the perfect soil conditioner to use or you want to experiment with other amendments you can try the following:
- Coconut coir
- Manure
- Compost
- Pine Needles
Whatever your choices are when it comes to great gardening, just remember that the main ingredient is love. And you can’t buy love!
FAQ
Should I add peat moss to my vegetable garden?
You should definitely add peat moss to a vegetable garden, especially if you need acidic soil. Adding peat moss to your vegetable garden soil creates acidic and water-retaining properties that certain vegetables will take advantage of. For example, strawberries, tomatoes, and blueberries grow very well in acidic soil.
What plants should you use peat moss?
Peat moss is ideal for vegetables and fruits that require an acidic climate due to its low pH. Plants such as tomatoes, azaleas, and hydrangeas are just a few examples, to name a few.
Why gardeners should not use peat Moss?
Gardeners should not use peat moss because of the environmental effects it has on sourcing it. Many environmental protection agencies have lobbied governments and businesses to stop sourcing peat moss for the purposes of gardening and horticulture. Sourcing peat moss has detrimental land and environmental effects for wildlife, carbon stores, effects of flooding and deterioration of local water sources.
Can you mix peat moss with garden soil?
Yes, you can mix peat moss with garden soil. Peat moss is a great soil amendment for any potting mix and garden soil, as it lowers the pH level, helps retain moisture, and since it is organic, peat moss will add nutrients to the garden soil.
Can you add too much peat moss in a garden?
Yes, adding too much peat moss, like any soil amendment, can be detrimental to certain plants. Peat moss will lower the pH level in the soil, making it acidic. Fragile plants that do not do well in acidic soil will not thrive.
References
Lindsey Hyland grew up in Arizona where she studied at the University of Arizona’s Controlled Environment Agriculture Center. She continued her gardening education by working on organic farms in both rural and urban settings. She started UrbanOrganicYield.com to share gardening tips and tactics. She’s happy to talk about succulents and houseplants or vegetables and herbs – or just about anything in a backyard garden or hydroponics garden.
