Why I feel we should never use peat as a soil amendment

I imagine that in some parts of the US you would have to heavily amend the soil to grow blueberries or other acid-loving plants. I would want to ascertain what other options people have and what odds they are fighting before dismissing their preference for peat out of hand.

 

I think peat is overused. We pay significant amounts of $$ for bagged "topsoil" that appears to be 95% peat, a handful of fertilizer, and the rest is "who knows what". Peat only retains moisture if it is planted in a situation where it is "kept" moist at the base of a planting hole a couple of feet down. Some of my clients use it in sunny, exposed rockeries to "hold moisture" when all that happens is that the sun dries it out and then acts as a sponge - wicking moisture "away" from the plant roots as it dries and creating cavities all around the planting pocket through shrinkage. You really need to understand the properties of peat in order to use it beneficially.

My opinion, for what it's worth!

Wynn

 

Attack on 'dusty' peat moss.
Peat moss use to have a chunky texture years ago, the stuff sold today is simply dust, any absorbent properties are probably not even present. The manufactures slurry the product for ease of handling, and this destroys the old chunky texture. I put ten bags about four yeara ago to mix with my garden soil in a relatively small area. It simply disappeared and I felt it did absolutely nothing beneficial.

How to Make Soil More Acidic (Decrease pH) Peat moss is acidic and will reduce pH, but there are other methods.

Some ornamental plants and fruit plants like blueberries require an acidic soil. To make your soil more acidic (decrease its pH value) you can use either aluminium sulphate or sulphur. Aluminium sulphate is the quickest acting as it will increase the acidity as soon as it disolves into the soil. The downsides are though that its effects can be short term and it is possible to over-apply it.

The more recommended but slower way to increase your soil pH is to use sulphur. Sulphur converts to sulphuric acid with the help of bacteria in the soil but this takes time depending on factors like the presence of bacteria, texture of the soil and moisture levels. This could take months if conditions are not ideal.

For my peppers (like a ph around 5.5) I feed them a cup of vinegar in water periodically during the summer, in the home garden. This is very local treatment. http://etooj.notlong.com/ 31 August 2007 Harvest of the produce from five plants.

Another way to decrease the pH is to use evergreen needles. There is no shortage of these in most areas.

My preference for making friable soil in the garden is small wood chips (rather than peat moss) mixed in the soil, along with compost. I find these chips disappear in a year, and I add about three inches evey year, and the level of soil never increases. There appears to be sufficient nitrogen in the compost to balance out that used in decomposing the wood chips, plus I plant a fall crop of red annual clover that fixes soil nitrogen. The proof is in the pudding. Here is the garden. http://poqua.notlong.com/ 27 June 2007 Zone 5B.

 

I've always favoured coffee grounds for acidification, since they're high in nitrogen too...

I'll weigh in because I've never really liked peat moss as a soil additive - I prefer to amend yearly with compost and grass cuttings, then adjust acidity for the plants that need it with coffee grounds as I mentioned above. Looking at how peat is mined gives me the heebidy-jeebidies and makes me glad that it's not available here in EC.

 

Hey all,

I'm surprised that no one has mentioned coir yet. It's one of the most interesting peat alternatives on the market these days.
Yes, compost is (almost) always a far better soil amendment but it also takes time, 'ickiness', & effort to produce. For that reason, coir & other similarly pre-fab products, are a far closer match to the ubiquitous bags of plastic wrapped peat that we've used for decades.
Anyway, this is something I posted in a thread last year:

Now, whether or not you agree with the use of coir, I think it's vital that we, as plant-lovers, don't buy or promote the use of peat - and let me reiterate why:
- The avg depth of peat bogs across the world is 1.3-1.4m
- It takes roughly 1yr to grow a layer of temperate peat bog 1-2mm thick (=0.001-0.002 metres). That's the equivalent to just 10-20cm (0.01-0.02m) added per century.
- Industrial extraction removes (ahem, "produces") more than 4,000,000-5,000,000 metres^3 of peat globally per year. And a very large proportion of that is sold to gardeners.
- At that rate, it would take tens of millions of years for peat bogs to regrow the volume of peat that we extract EACH YEAR.
- When there are so many better, cheaper, & more sustainable alternatives, it really makes no sense for us to continue using peat as a soil amendment or potting medium.

Well, I really apologise for the length of this post but I hope my treatise ;) has helped encourage or even convince someone to abandon peat in favour of its many (better) alternatives.

 

The problem with this thread is in the title. It should be "Why I feel I should never ..." The current title attempts a religious conversion. Do what you want but don't tell me what I should do.

Sphagnum peat moss is a superior product and there is nothing else that is as good for as many applications. At the current usage we will not run out of it before the next Ice Age covers all the peat bogs in the north.

So with that, I will now go out to the greenhouse and continue seed starting using a sphagnum peat moss mix.

 

Coirpeat product at first look appears to accomplish what peat moss does not. But coconuts do not grow in Canada, and there are few if any importers of coirpeat.

No local garden Supply Houses sell the product.

When and if coirpeat becomes as common at Walmart as peat moss, it might have a market, until then it is a wishful pipe-dream.

 

It is more than just 'using up available peat'

it is unlocking huge amounts of CO2 into the air while clear cutting peat land ecosystems which sends damaging ecological cascade throughout the globe as a consequence.

it is about draining peat lands and disturbing water tables as well as those directly surrounding the damaged peat lands

 

I'm glad coir was brought up because I'm a soil-less grower with both my vegies and flowers. I add Pro-Mix BX to my compost to make it go twice a far. Pro-Mix BX is composed of:

Canadian Sphagnum Peat Moss (75-85 % / vol.)
Dolomitic & Calcitic Limestone (pH adjuster)
Endomycorrhize (Mycorise® Pro)
Macronutrients
Perlite — horticultural grade
Micronutrients
Vermiculite
Wetting Agent

I have been using this 50/50 ratio as well as 100% Pro-Mix BX with liquid nutrients for years and I've never had a plant die on me or even get a nutrient issues. by liquid nutrients I've been using both peters 20-20-20 & home made compost tea from the run-off of my compost. when i attempted to use coir, I transplanted my seedlings from pro-mix to coco-coir & i notice my plants became very yellow which i suspect is a PH issue. when i noticed the problem i took off to the local hydroponics store and picked up some PH up and that fixed the problem immediately.

I guess in all my rambling it all boils down to if you are a soil grower and you decide to use coco coir, mix lime or crushed oyster shells in your mix before potting your plants or else you will have the same acidic ph issues as i had. if you correct the issue at the "root" of the problem, you won't have to adjust the ph with liquids like i choose to. with that said i will probably still use my favorite soil-less base, but i understand where your coming from with this post (concerned about the environment). happy growing everyone

 

I've found it at Canadian Tire! Canadian Tire is still more common than Walmart, right? But this was a Canadian Tire in Victoria, BC, your millage may vary.


The coir I've seen around here was sold as dehydrated bricks. In brick form it looks a little pricey, but it expands hugely when you add water. I'm very happy with it so far, it has more "texture" than the peat you usually get and is much less dusty.

One of the problems with finding coir is that when it is sold in small bricks, rather than big bags or bales like other soil amendments, it often isn't placed in the same place as the bags. In Canadian tire I found a little display of the bricks placed on a shelf under some gardening tools, no where near the bags of soil, compost and peat. If you are looking for it and don't see it, it can't hurt to ask -- they may have just placed it somewhere strange. I've also seen it at the local compost education center, http://www.compost.bc.ca/store/index.html so you might try looking at similar places.

An advantage to the dehydrated bricks is that they are much, much easier to handle, carry, and get home than the moist bags of compost and soil, much less the gigantic bales of peat. Why haul water around if you don't have to? Even if you are riding a bike or taking the bus you can easily carry home a bunch of dehydrated peat bricks because they are light and compact. You can rehydrate them right where you plan to use them, saving some back strain.

 

Durgan, while coir may not be available in Walmart yet (or is it?), the first place I saw it was in another megastore: HomeDepot! And, just as Angela Christine thought, the coir was kept on a shelf near the greenhouse/orchid/fertilizer products and not with the giant bags of compost & peat.

Even if Brantford doesn't have a source for coir, Hamilton & Toronto surely do. And, no matter where you live, the owner/manager at any decent nursery should be willing to investigate (&, hopefully, sell) ANY product you show a serious interest in. Before trying HomeDepot, I checked for coir at my fav local nursery. The owner had never heard of the stuff but he showed genuine interest when I explained what it was & why I preferred it over peat. And, now, that very same nursery stocks at least two different brands of coir and even displays them right alongside the peat!

So, don't wait for Walmart: try & ask elsewhere (preferably at a small local business)

 

I don't condone any strip mining for peat but it would appear to be very sustainable given your numbers....you forgot to include worldwide square miles of peat bogs in you calculations:

- 1,000,000 square miles of peat bog (low estimate, I've seen quoted 2 million & 9 million, if anyone has a more accurate figure, please reply)
- 1 mm annual depth increase
= 2.5 billion cubic metres of peat growth each year

- 50,000,000 cubic metre harvest
= 52x more peat accumulates in a year than is harvested. If you assume an average 3 month growing season, it takes just short of 2 days of summer growth to accomodate our annual peat harvest.

Simon

 

You can't lump all peatlands into one. There are tropical, temperate, and arctic peatlands. They are all treated differently by humans.

Peat for horticulture is dug unsustainably, for one, and for another, it unlocks vast amounts of CO2 into the air, and requires a great amount of energy in processing.

This isn't an issue of running out of peat moss to use for horticulture, it's about using it when it is not needed, and its about wiping out regions of wildlife for a wasteful and damaging process that takes away hundreds of years of growth in a harvest. It only accumulates 1mm or so a year, and harvesting a plot like a mine wipes out hundreds of years and is permanently damaged.

Tropical peatlands are under even more attack and release even more co2. If you look at the statistics they are under serious threat.

Adding to the carbon in the air by harvesting millions of cubic tons per year for horticulture alone, and draining peat bogs (which *rapidly* speeds decomposition and therefore massive co2 liberation) has serious consequences.

That's why it is not sustainable in any way to be using peat moss for horticulture.

 

http://www.imcg.net/docum/Peat_ccgap.pdf

 

I stand by the numbers....

The article quotes 400 million hectares ~ 1.5 million square miles. Since the majority of peat lands occur in temperate zones, the calculation assumption of 1 million square miles of temperate peat is probably a slight underestimate.

Even if accumulation is 0.5 mm/yr, it would still only require 4 days of summertime growth to accumulate 50 million cubic metres of peat (the estimated annual harvest).

What does concern me however, is the quote of 5 million hectares of peatland affected for peat harvesting. Something is fishy with either that number or the 50 million cubic metre harvest number because it works out to an annual harvest 1 millimetre thick. Granted, not all the peat bogs drained are 100% utilized for harvest, but to drain 1000x more land than required for an annual production rate seems terribly inefficient and even the most pillaging of corporations is unlikely to do that.

I would also be very surprised if coir production could be increased sufficiently to meet the current world demand and 100% of the horticultural demand without causing its own environmental problems. Think about clearing land for coconut monocultures, finding markets for the byproducts of coir production (ie. the rest of the coconut), etc.

I prefer more scientifically balanced views and the literature that's been presented to date takes a very negative bias on the topic. That factor alone tends to make me skeptical of conclusions being presented.

 

Just a few comments in reply to smivie - and I really really hope that this doesn't come across like I'm some sort of snarky, smart-alec flamer... I'm just a biologist with OCD & insomnia ;-)

1. I don't think we should even try to re-assess the numbers b/c, as smivie pointed out, it's hard to find clear data for all the variables (area, depth, harvest volume etc). If someone can find a single reliable "scientifically balanced" source (esp avoiding enviro groups, garden groups/stores, and peat & coir 'producers') with all of the data needed to do the math, then perhaps we can compare growth vs harvest rates. Till then, though, I think we're probably just wasting our breath (uhhh, key strokes?)
2. As for the info being unbalanced/biased, I'd agree but would also argue that the bulk of the info & statements in this thread are automatically biased - not because their conclusions or accuracy are biased, but because all of the "facts" and "details" have been presented by anti-peat posters. Case in point: the thread's title. So, to even things up a bit, maybe the pro-peat (or anti-alternatives?) people would want to find some facts (not anecdotes) to suggest that peat harvesting is sustainable, not environmentally harmful, & not replaceable.
3. Very little of the info presented here is actually drawn from "literature," per se. Most comes from misc websites or pamphlets, not a publication, review or study.
4. Similarly, if smivie wants "scientifically balanced views" then blogs, NGO & corporate websites, and fluff pieces (where most of the info in this thread comes from) are definitely not the place to look and shouldn't really be judged as such. Once again, maybe some thread-readers will feel inspired to find published & peer-reviewed scientific articles, scientific conference proceedings, or reputable media stories (based on hard facts & quotes). Because there's GOT to be at least one grad student in the world who's looked into the process, impact, & sustainability of peat extraction - or, better yet, someone who also compared peat to alternative products!! Even though I'm anti-peat person, I'd still be interested to read something like that.
   {edit: the madehow.com link (below) cites a scientific study presented at a 2000 UN conference ("Reuse of By-Products in Coir Industry: A Case Study") but that's no longer avail online. arg}
5. And, finally (phew), horticultural-grade coir is itself a by-product product, being the dust (aka pith) that remains once a coconut has been husked, processed, had its 'meat' removed and its 'coir layer' separated out for the manufacture of rugs, rope, etc.
   See:
   --http://www.madehow.com/Volume-6/Coir.html **good**
   {edit: it links to a UN report that describes all of the processes & products derived from the coconut}
   --http://en.wikipedia.org/wiki/Coco_Peat

 

Well said!

Does anyone know if worldwide the coconut crop even generates enough coir byproduct to support current coir markets & the potential horticultural demand (as a complete peat replacement)?

 

One comment on coir.

Although it is a very useful product you have to be very careful where it originates and how it is treated. About 7 or 8 years ago ground coconut husk was lauded as the next big orchid potting media. The problem for the importers was much of it was being "cleaned" with salt water taken directly from the ocean. Sea water is much more abundant on most islands than fresh water. I personally lost several hundred orchids due to this fiasco. I changed a bunch of my collection over to the coconut husk while we lived in Florida and within a few weeks they began to decline. We could not figure out what the problem might be until one local supplier of the ground coconut announced to all their regular customers the stuff was filled with salt! Orchids will not tolerate salt!

A lot of orchid supply places now specify and guarantee their product to be salt free. But there is no guarantee you won't get salt water "cleaned" coir from other sources.

And Smivies and Fern 2, I find your points extremely well researched. I have always disliked "numbers" thrown around without the detailed information needed to make sure they are applicable.

 

I use peat to break the clay structure of the soil and to make the soil more "lighter" better drainage.

But, I hear where you are coming from.

 

This is a most interesting thread and I'm still absorbing and processing all of the replies.

I was particularly interested in Karin's reply, since it corresponds with my own view that activism is a little like fertilizer. A little can be good, but too much can burn the 'roots' and the plants (converts) one hoped to cultivate die off.

Humility, never a tasty dish to eat at the best of times, is especially important if one is proposing change. The promise of Biofuels as an alternative to inorganic energy has been met: various countries around the world are increasing their production of crops that can be used for ethanol production. Unfortunately this alternative was devised and 'sold' in advance of the problems associated with such production being fully appreciated. When the food chain is diverted to producing energy for machines and not people, the result is higher food prices - which bodes ill for sustainable peace amongst the world's people. There is also the risk that areas one hoped would not be used for cultivation (e.g. rainforest) are being used to grow 'biofuels.'

I thought of this when reading about the peat alternatives proposed. The idea that 'coir' (have I got the term right?) comes from byproducts of another industry - coconut processing - is attractive, but possibly many of the same pitfalls are lurking.

Consider the instance in which market demand for peat/peat alternative isn't satisfied solely by 'byproduct' of coconut processing. If the market converts completely to coir, this could lead to an increase in land being used to produce coconuts, i.e. coconuts being grown solely to produce 'coir' on a large scale. Large scale production of anything tends to have large-scale impacts on local economies, land use, and energy consumption (to export the product) etc. etc.

Will such effects of coir production constitute a lesser evil than peat mining? I think any solution devised will quite likely have a 'tipping point' i.e. a point at which the net benefits are outweighed by the expense, in either financial or environmental terms. So a cautious compromise seems to be one in which one doesn't abandon peat entirely, but balances one's consumption of it with purchase of a variety of alternatives.

 

If I had legs I would stand up and applaud your response Moth1! I am an environmentally conscious person. I do all I can to conserve. But I find it very frustrating when groups of people bond together solely for a "cause" without fully thinking though the effects of that cause! Enormous amounts of ground water are being used that cannot be replaced by corn farmers in totally dry regions of our country simply to produce bio fuel. Is that healthy for the environment? Stopping production of peat may be good for the people who see the holes in the ground but is it good if all the coconut trees in the Caribbean are cut down and ground up? I used to live in the Caribbean and believe me, people will do what they find profitable in those countries! If the trees make more money ground into chunks rather than producing coconut, they will be ground!

Ideas are fabulous. But what happens to those ideas when they are implemented is equally important. And right now all of us are paying dearly for our refusal to access our own natural sources of fuel and simply allowing all the Arab countries to build those ugly oil wells. Soon we will all be paying $5 or $6 per gallon. And all we can do is complain because we as a group of environmentalists (including me) are far too short sited.

All we can see is the "trees"! We must think beyond those "trees"!

 

Bravo.

 

Using Peat Vs Coir? Oak Catkins?

A very interesting thread. Until this year I had never worried much about the effects of peat harvesting. Does anyone know exactly where the "Canadian" peat available in BC comes from?
Another point against using coir here in North America is that, even if the global supply was adequate it has to be transported from far away using lots of fossil fuels. For that reason I feel we should be trying to minimize our consumption of exotic fruits like coconut and its coir byproduct.
This spring for the first time I noticed large clumps of a soft, dry,lightweight material on the ground which seems to be the male catkins of oak tree. Looking at it I wondered if it would be suitable to mix in with heavy soil to lighten it up or to use as a moisture retaining mulch. Has anyone ever used it in their gardens?

 

See, and my support for Coir comes from living in a country where it is a natural byproduct of the coconut sales industry, not an exotic import. It's actually much easier to find it here than peat moss, but more common still is finely shredded bamboo. This does a double service to the gardeners of the country, because what is available is the byproduct of the removal of a pest species.

Here's a word on Coir, just to play devil's advocate - Ecuador is a coir producing country, but here the term here refers to any palm-fruit husk fibre usable as soil amendment. Much of our domestic "coir" is actually pressed oil-palm husks, which we have in abundance due to our much larger palm-oil industry.

Since Coir is properly only the husks of the mature coconut fruit, and not the tree itself - and it's a small market here and larger abroad, it doesn't generate the kind of cash that makes people convert land to coconuts. The nice thing, though, is that coconuts will tolerate soil conditions that would kill other crops (ie high salt, low nutrients), so they tend to be farmed, when they're farmed on large scales, on land that is otherwise not usable for food production. This said, most of the coconuts sold in Ecuador are not true coconuts, but a large Amazon palm fruit which is strikingly similar in size and flavour. Coastal (true) coconuts tend to get exported.

 

Whoever thinks peat doesn't melt away like compost should try gardening in somewhere warm, alright hot. It's gone just as fast as compost. It does acidify the soil, but then pine straw or a little sulfur acidifies it better and longer. In the heat it doesn't retain water, if anything it forms a barrier and allows the water to run off or evaporate.

Peat has almost no nutritional value to add to the soil when compared to compost - mulch - mushroom compost - worm castings, etc. There is no financial gain to using peat, it's more expensive then many other soil amendments.

Then there are all the environmental reasons not to use peat. Of course if you're someone who doesn't believe in global warming -- well i'm not going to get started on that diatribe. My point is there is little benefit and little justification to use peat.