Why Gardeners Are Going Peat-Free — Empress of Grime
Peat has lengthy been a staple in business potting mixes, however rising environmental considerations are prompting gardeners to hunt extra sustainable, peat-free options.
We even have guides on composting (and methods to hold it rat-free) together with sources on methods to buy soil and manure. For brand new gardens, additionally attempt our helpful soil calculator.
Peat within the Headlines
Using peat in gardening is a sizzling subject proper now—particularly in the UK, the place a ban on retail peat gross sales is anticipated throughout the subsequent yr or so. The Royal Horticultural Society has additionally introduced it should now not permit peat at its backyard exhibits.
Right here in North America, the problem hasn’t gained the identical traction—although consciousness is rising.
Many gardeners don’t even notice they’re utilizing peat. Even if you happen to by no means purchase peat moss as a stand-alone product, chances are high it’s nonetheless in your backyard.
That’s as a result of peat is a typical ingredient in most business potting mixes—until labeled peat-free. It exhibits up in bagged and bulk soil, seed-starting mixes, and the rising media used for nursery crops.
However I’m getting forward of myself. Clearly it’s available and helpful, so what’s the massive deal? Why is peat being singled out as an issue?
The problem just isn’t the peat itself. It’s the way it’s mined that’s the issue.
The extraction of peat primarily decimates wetlands—an important a part of our ecosystems—and life on earth.
Let’s take a look at peat—what it’s, the way it’s used, and why peat extraction raises environmental purple flags, even right here in Canada the place huge peatlands nonetheless exist.
This text is predicated on the episode Peat in Gardening: What’s the Drawback?
from our podcast, Two Minutes within the Backyard,
accessible wherever you discover your favourite podcasts.
Peat 101
What’s Peat?
Peat is barely decomposed natural matter. Particularly, it’s natural matter from wetlands that has accrued and partly decomposed over the course of centuries or millennia.
Sphagnum Peat
Lately, once we discuss peat, we’re virtually at all times referring to the Sphagnum genus and its lots of of species. Different natural matter can get into the peat—bits of lifeless crops, microbes, bugs—but it surely’s principally Sphagnum.
Like all mosses, Sphagnum mosses are crops with out roots, in order that they absorb water and vitamins by way of their leaves and stems. Mosses have specialised cells that may maintain a variety of water like a sponge.
Why Peat is Gradual to Decompose
It’s fairly attention-grabbing why peat doesn’t simply rot and disappear into bogs.
In a compost pile, we count on natural matter to decompose inside a couple of months to a yr. So how is it that peat stays solely barely decomposed after centuries?
There are a number of causes:
- Low Oxygen | Peatlands are moist and waterlogged and that water incorporates little or no oxygen. There are oxygen atoms within the water molecules, however these aren’t accessible as oxygen and there’s not a lot dissolved oxygen within the water. This lack of oxygen significantly reduces the microbial exercise wanted to drive decomposition.
- Carbon Heavy | Peat could be very carbon-heavy. Its excessive carbon-to-nitrogen (C:N) ratio is just like straw. We don’t normally consider moss as a “brown” in composting phrases, however it’s. There’s not a lot nitrogen (“inexperienced”) to steadiness issues out, which slows decomposition even additional.
- Acidic | Residing Sphagnum mosses create acidic circumstances. They don’t play nicely with different species, and their acidity additionally slows decomposition.
- Chilly | Many Sphagnum peatlands are in colder areas, the place microbial exercise slows down—identical to in a compost pile throughout winter.
So even after centuries, peat solely decomposes somewhat. In the meantime, extra is added yearly as mosses attain the top of their life cycle, however the quantities are minimal. In Canadian peatlands, this pure accumulation is lower than a millimeter a yr—sometimes concerning the thickness of a bank card. However, over lots of or hundreds of years, that provides as much as deposits a number of meters thick.
As quickly as I heard “lower than a millimeter a yr,” a purple flag popped up. However environmental considerations weren’t on our radar again when peat entered the gardening world.
Historic Use of Peat in Gardening
Peat has a protracted historical past in gardening, particularly within the UK the place suggestions to make use of peat as a soil modification date again to the early 1800s.
We begin seeing peat talked about for agricultural and a few horticultural use within the U.S. by the Twenties and 30s.
It actually took off within the Nineteen Forties and 50s.
- A 1959 version of “10,000 Backyard Questions Answered by 20 Consultants” incorporates over 400 references to peat and peat moss.
- Rodale’s “Encyclopedia of Natural Gardening” from the identical yr mentions it over 200 occasions.
It was round that point that peat turned the bottom for a lot of potting mixes, normally blended with supplies like perlite or different parts.
Why Peat Grew to become Fashionable
We all know natural matter is helpful for soil, enhancing construction, drainage, lowering compaction, supporting microbial communities, and extra.
However why did peat specifically change into the go-to base for potting mixes way back to the Fifties?
That reply is two-fold. The fascinating qualities present in peat and the advertising and marketing.
- Glorious water retention | Peat is gentle and fluffy—nice qualities for a potting combine. However for one thing so gentle, it holds a formidable quantity of water—sometimes 15 to twenty occasions its weight. That’s because of these specialised cells in Sphagnum.
There’s a draw back: when peat dries out, it turns into hydrophobic. Water will bead up or run off as a substitute of soaking in. So, you need to keep away from letting it dry out utterly. However so long as it stays moist, peat retains soil moist longer whereas nonetheless permitting air to flow into—very best for container rising.
- Fewer Pathogens and Weed Seeds | Peat is commonly described as “sterile,” although that’s the gardening use of the phrase. It’s not sterile within the microbiological sense, however probably incorporates fewer pathogens and weed seeds than compost or backyard soil.
It additionally supplies virtually no vitamins—which is okay in a potting combine, the place you’re including fertilizer anyway. You don’t must account for any nutrient contribution from the peat.
- Broadly Obtainable & Cheap | Peat is straightforward to seek out in backyard facilities and on-line, and it’s not very costly. There’s clearly a variety of it being produced and offered.
Put all that collectively, and it’s no shock that peat turned so extensively used. It’s low cost, does what’s wanted, and accessible in potting combine in every single place.
Environmental Consciousness
Beginning within the Eighties, as we discovered extra about peatlands and their ecological significance, individuals started asking extra questions concerning the impression of peat extraction.
Relying in your viewpoint, it could be known as peat “harvesting” or “mining” — however both means, it’s extraction.
To extract peat for business use, wetlands are drained, and all these layers of peat are eliminated for processing. In the event you lookup movies, it’s the lavatory equal of clear reducing forests. The tip result’s a wasteland with little or no remnants of the previous ecosystem. Even with improved restoration strategies, the degradation attributable to peat extraction will proceed for many years.
And all that carbon that has been contained for eons is launched within the ambiance.
Carbon Sequestration
Carbon sequestration is a fancy subject. Greenhouse gases, notably carbon dioxide, are important for all times on Earth, however extra contributes to world warming.
Carbon dioxide ranges have risen over 30% since 1965, inflicting rising temperatures and excessive climate occasions.
We can assist counter this by lowering emissions and by storing carbon in “carbon sinks” like soil and crops.
And guess what does an distinctive job as a carbon sink?
Peatlands.
Peatlands retailer extra carbon than all of the world’s forests mixed
Peatlands are wonderful at storing carbon. They retailer extra carbon than all of the world’s forests mixed. About one-third of all soil carbon is in peatlands, and it bought there naturally over hundreds of years.
If left undisturbed, peat decomposes slowly and continues to sequester carbon. After we extract peat, that very same carbon is—you guessed it—off into the ambiance the place we don’t need it.
Peat Extraction is Not Carbon Impartial
Some argue that composting additionally releases greenhouse gases—as do many different horticultural practices. And that’s true. Natural matter releases greenhouse gases because it decomposes, and there’s actually no means round that.
With compost, the carbon being launched was already just lately within the ambiance and is simply going again the place it was, principally in the identical kind. That’s why composting is taken into account to be almost carbon-neutral. Peat, however, incorporates historic, sequestered carbon that’s been safely tucked away for millennia.
And the whole extraction course of and distribution cycle has its personal heavy footprint (which can even be true for a lot of different issues we use within the backyard).
There’s no disputing that many facets of the gardening world are exhausting on the surroundings. However peat use requires the discharge of what was and principally would have remained sequestered carbon. Peat degrades very slowly in peatlands, however as soon as it’s been extracted, the carbon within the peat is launched into the air comparatively shortly.
What Restoration Actually Means
You’ll generally hear the soundbite saying (excellent news!): peatlands will be restored.
Sadly, “restoration” after peat extraction doesn’t imply peatlands return to their authentic state. That doesn’t occur. Restoration simply means making them considerably ecologically useful once more, maybe getting Sphagnum to regrow on a part of the land, even when it’s far lower than earlier than.
Restoration efforts are higher right now than previously however nowhere close to what’s wanted.
It could actually take a long time for a peat extraction website underneath restoration to carry extra carbon than it emits. And getting again to pre-extraction carbon ranges will take centuries — or longer—if ever.
Some restoration makes an attempt fail completely. A 2013 examine discovered that 43% of websites didn’t return to being Sphagnum-dominated after 10 years.
Plus, restoration typically requires donor websites to supply plant materials, which causes further land degradation, disrupting a brand new space whereas making an attempt to restore an outdated one. And plenty of peatland crops received’t develop once more on websites after they’ve been restored.
UK & Eire Versus North America
Within the UK and Eire, about 80% of peatland has been degraded. Throughout Europe, the place peat is a standard gasoline supply, it’s about 50% — the best on any continent.
This problem hasn’t acquired almost as a lot consideration in North America.
The U.S. will get 90% of its horticultural peat from Canada, the place solely about 2% of peatland has been degraded. That sounds promising till you notice this is because of remoteness not restraint.
A lot of Canada’s peatland is in arctic or sub-arctic areas or simply in distant northern areas the place extraction could be too expensive. A variety of the peatland can be on Indigenous lands or conventional Indigenous territories the place extraction would face vigorous resistance.
The Peat PR Machine
The peat business has pushed again with PR campaigns, typically focusing on gardeners with emotional appeals disguised as reasoned argument.
The messaging is selective, downplaying the environmental impression.
I do know I used to purchase into a few of it.
You’ll hear issues like: “We now have loads of peat. Extra is made yearly. Which means it’s sustainable.”
True sustainability means not utilizing sources in a means that compromises the wants of future generations.
However sustainability isn’t about provide. It’s about preserving peatlands to allow them to proceed to retailer carbon, handle water, and assist biodiversity together with different very important ecological features. With out them, we’d be dwelling in some apocalyptic spoil.
And generally it appears like a race to the underside. Or an environmental sport of rooster.
Sustainability means not satisfying our present wants on the expense of the wants of future generations, and that’s the other of what peat extraction does. It’s purely about satisfying present wants and the associated fee is environmental deterioration that may final for many years and even centuries.
Supporters speaking up restoration underplay the problem and scale. The restoration they’re referring to just isn’t a return to what was. That credit-card skinny layer of moss that may regrow annually can not undo the injury executed. At finest, you get a partial, moss-dominated wetland after many, a few years. Can we actually say that’s restored? And can it matter after that a lot time?
What About Agriculture?
Peat supporters typically level out that agriculture has degraded extra peatland than horticulture. And that whataboutism is true. However it doesn’t make horticultural peat extraction any much less regarding.
Most agricultural conversions occurred a long time in the past. Horticultural extraction continues right now.
For impression, whereas neither is helpful, the method for changing peatlands into farmland normally leaves the peat (and carbon) within the floor.
Horticultural extraction, nonetheless, removes the peat (and releases the carbon), typically digging it out many meters deep. That’s lots of of hundreds of years of accumulation gone.
Abstract
Peat has performed a significant function in potting mixes for the previous 70 years—however we now perceive the environmental value is steep. Extracting peat destroys ecosystems. Restoring peatlands can take a long time and even centuries, and the carbon launched throughout excavation is difficult to justify.
The pending U.Ok. ban has prompted the event of peat-free options which we’re beginning to see right here too. Like most adjustments, it’s imperfect—however a needed shift towards extra accountable practices.
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~Melissa the Empress of Grime ♛
