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rt_peasant

Peat Moss and Nitrogen

rt_peasant
14 years ago

I'm amending my garden soil this spring with 1.5" of peat moss. Will the peat moss decompose and rob the soil of nitrogen in the process? I'm wondering if I need to add extra fertilizer to offset any lost nitrogen. Or is the opposite true, that the peat moss will actually contribute nitrogen in the short term?

Comments (24)

  • bpgreen
    14 years ago
    last modified: 9 years ago

    Peat moss is probably not the best thing to use in CO. It's too dry, so the peat moss will dry out. Once peat moss dries out, it repels water. Not what you want.

    If you're tilling it into the soil, you might be okay (assuming you keep the garden moist).

    But peat moss is nearly completely decomposed, so it won't do much either way in terms of N.

  • tsugajunkie z5 SE WI ♱
    14 years ago
    last modified: 9 years ago

    Most likely neither. No N to really contribute and too acidic for the microherd to eat and tie up a lot of N all at once...generally. But you better duck 'cuz I fear there's flak comin' your way.

    tj

  • Kimmsr
    14 years ago
    last modified: 9 years ago

    Peat moss has no nutrients so if you add this non renewable resource to your soil (there really are better materials available a less cost) you will need to add nutrients in some form.

  • gardengal48 (PNW Z8/9)
    14 years ago
    last modified: 9 years ago

    Because peat moss is so slow to decompose, it makes no significant draw on existing soil nutrients. It also doesn't contribute to nutrient levels in any significant manner. Any need need to fertilize will depend entirely on what existing soil nutrients levels are and what your crops require, not because you are adding (or not adding) peat moss.

    It is about 80-95% organic matter, will help to retain soil moisture and will lower soil pH if incorporated into the soil, so many do use it as an amendment for these purposes. If you do choose to add peat, make sure it is moistened before using and do incorporate it into the soil.

  • tapla (mid-Michigan, USDA z5b-6a)
    14 years ago
    last modified: 9 years ago

    Those 'absolute' and ideological statements are very difficult to prove, or even present a convincing case for. Peat moss assuredly has nutrients, though it may not be the best or ideal source - and I hope I'm not the only one that thinks the 'non-renewable' argument against using peat is absolutely silly.

    Al

  • gardengal48 (PNW Z8/9)
    14 years ago
    last modified: 9 years ago

    Of course you are not, Al. After researching the issue, many share the same belief, although espousing that well-documented concept on this forum is bound to get those who believe otherwise seriously riled up! Hence the above remark about the flak flying :-)

  • Lloyd
    14 years ago
    last modified: 9 years ago

    "I hope I'm not the only one that thinks"

    There are a few that don't "think" and they become apparent relatively quickly. ;-)

    Lloyd

  • lazy_gardens
    14 years ago
    last modified: 9 years ago

    RT - If peatmoss gets dried out, it has the soil amending qualities of shredded styrofoam.

    Can you get some local composted pine bark fines, or horse manure or something?

  • jonhughes
    14 years ago
    last modified: 9 years ago

    Al, Gardengal, and Lloyd

    I consider you all to not only be the VOR (Voice Of Reason) but awesome contributors to this Forum....
    Question: Are we being "Punked" ???
    Is Ashton Kutcher nearby ;-)
    I know that Kimmsr has been a part of this forum for quite a while now.... but are you positive he isn't simply a computer software program....that needs to be re-booted ;-)
    Even with the wisest counsel by you and others...he continually beats that same drum..... I think that line of thinking would die out, if he would just "let it go".... OY VEY.... Whatever

  • Lloyd
    14 years ago
    last modified: 9 years ago

    Long story Jon, it's being going on for years (even before I got here and on other forums as well), best not to dwell on it. A persons forehead can get awful tender hitting it against a brick wall.

    RT, sorry for the 'aside' on your thread.

    Lloyd

  • rt_peasant
    Original Author
    14 years ago
    last modified: 9 years ago

    Wow, I didn't realize that I'd need a "flak" jacket to post in here. Thanks all for the useful info!

    bpgreen, I am planning to till the peat moss into the soil. You're right, it is dry here in Colorado. I usually cover the garden with a layer of grass clippings to hold the moisture in, and I'm hoping that the peat moss will keep my soil a little looser.

    tsugajunkie, our soil here in CO is very alkaline and tends to get more alkaline with watering. The acidic peat moss should help in that respect.

    kimmsr, you say there are better materials available at less cost. I assume you're talking about composted leaves or other such material? That's really not available to me, since my compost isn't close to finished. I needed something available now, and peat moss seemed like a good choice.

    gardengal48, you said make sure that the peat is moistened before adding it to the soil. We still have 4-6 more weeks of snowy weather, and I was counting on snowmelt to moisten the peat moss. The slow melting action usually soaks the ground. Does that seem reasonable, or am I missing something?

  • natschultz
    14 years ago
    last modified: 9 years ago

    SPHAGNUM Peat Moss IS Renewable, PEAT is not!!!

    I'm am new to posting here, so I mean no offense, but here are the FACTS on "peat" and "peat moss."

    Sphagnum peat moss, the stuff you purchase as a soil amendment, is simply a slow-growing bog moss that is harvested responsibly up in Canada. It is harvested ALIVE!!! It is harvested on a rotation that allows the moss to regenerate itself. It is no less renewable than sustainably harvested timber is.

    You can even purchase live sphagnum moss, which is used in floral arrangements.

    Peat, on the otherhand is totally NOT renewable, and is very much an endangered product. "Peat" is actually the same sphagnum peat moss that grows in bogs, however it is the dead peat moss that settled to the bottom of the bogs over thousands of years, that is why peat bogs are called "ancient."

    Endangered peat is not used as a soil amendment, but rather it is harvested as a fuel source and burned in old homes and castles in European fireplaces. In order to harvest it the bogs are drained of water and then the peat (many feet deep) is cut like bales of hay and allowed to dry in the air.

    Ancient peat bogs are engangered, and the destruction of them is disaterous for the environment. Many ancient peat bogs were drained in the past simply to create fertile farmland. Many plants and animals evolved specifically in the peat bog environment and can survive nowhere else (many carnivorous plants). Also, peat bogs actually absorb a lot of carbon dioxide, just like the rainforests - both are irreplaceable.

    Many very well preserved ancient human bodies have been discovered in peat bogs, being buried there for religious rituals. In fact the oldest humans found have been discovered in peat bogs (I don't remember where the oldest one was, but most were in England, Ireland and Northern Europe). The extreme acidity preserved not only the hair and flesh, but clothing fragments and food items as well.

    By the way, after a few million years, that ancient peat is further chemically altered into another fuel source - oil!

    When harvesting new Sphagnum peat moss the ancient peat below the water's surface remains intact - it must, otherwise the new moss would not be able to survive, as the alkalinity (from new rainfall and runoff) would kill the new moss.

    So, in my opinion, purchasing peat moss as a soil amendment (not as a mulch or adding in bulk to soil as many people think they should do - that would be horrible for a low-maintenance garden), is actually benefiting the future survival of peat bogs. By creating demand for newly harvested peat moss, the harvesters have a valuable, renewable resource on their land, and this means that they have a very good reason not to drain the bog (and destroy it) to create farmland or develop it into condos.

    Why is Canada's peat moss sustainable, but Europe's is almost extinct? Because Europeans, especially in the North where timber was scarce, have been harvesting the peat for centuries. They did not realize the harm they were doing until recently. The Canadian settlers, on the otherhand, only arrived a few hundred years ago, timber was plentiful, so there was no need for peat as a heat source, and farmland was plentiful as well, so basically the bogs were left alone by humans until the discovery of sphagnum as a soil amendment (it was used medicinally and as a preservative first).

    So yeah, use peat moss in moderation as a TEXTURE amendment, but use other organic products like mulch, compost, straw to create a healthy soil. Just remember that it grows slowly and the production can not expand to keep up with demand (peat bogs cannot be re-created, trust me, I've read every research paper and experiment that has been tried).

    As for your question on amending garden soil, you didn't give any info as to what was wrong with it in the first place. Leaf mould will mold moisture just as well as peat moss, add nutrients to the soil, and most importantly not dry out as badly.

    Personally, I just bought a bale of peat moss today, only because we have had three horrible days of record-breaking rainfall and I finally got fed up with the Poltergeist swimming pool in my backyard and decided to did out a drainage pit in the clay soil. I filled an 8x8 unfinished raised bed with clay almost 2 feet high, and then I had no choice but to start adding clay to the beds I intend to plant in a few weeks. I turned the existing soil, added layers of organic matter between shovels of clay muck, but yesterday (the first day without rain) I couldn't turn the muck at all, it was way too dense. So I'm going to mix together a 1:1 mix of peat moss and lime and slowly turn that into the clay. My goal is simply to break up the clay particles, not to retain moisture. The lime will neutralize the pine needles and peat moss, but over time it should adhere to the individual clay particles and keep them from being a solid mass of muck when it rains and a solid rock when the clay dries out.

  • bpgreen
    14 years ago
    last modified: 9 years ago

    If you can keep the soil constantly moist, it's not an issue. But if it dries out, it becomes an issue. I don't think it matters whether you till it in or not. I stopped using it a long time ago because I'd find pockets of it completely dried out.

  • gardengal48 (PNW Z8/9)
    14 years ago
    last modified: 9 years ago

    If the peat moss is sufficiently moistened before incorporation into the soil as an amendment and mixed in thoroughly, you run little risk of it drying out and becoming hydrophobic. It absorbs 20 times its weight in water and releases it slowly, so it helps with moisture retention in the soil between waterings. The risk of repelling water is greatest if the peat is used as a surface mulch exposed to air and allowed to dry out.

    The continued snow melt should very well help to thoroughly moisten the peat - just make sure you open the bales sufficiently so the melting snow can be absorbed and doesn't just run off.

  • rt_peasant
    Original Author
    14 years ago
    last modified: 9 years ago

    natschultz wrote:
    "As for your question on amending garden soil, you didn't give any info as to what was wrong with it in the first place."

    I have clay loam soil that tends to get very hard in the heat of summer. I had it tested, and the lab results said "Low in organic matter. Add 1" of organic matter." So to loosen up the soil and add organic matter, I decided to amend the soil with peat moss, since my compost wasn't ready yet.

  • idaho_gardener
    14 years ago
    last modified: 9 years ago

    Peat moss is an ideal soil amendment. It will take some time for it to work its magic, but it will improve the soil structure. It will seem to melt into the soil, but as it does it will improve the soil.

    But keep the soil mulched with some sort of mulch to preserve the organic matter dissolved in the soil. Direct sunlight seems to bleach my soil, so I try to keep it covered with grass clippings.

    Here is a link that might be useful: Analysis of peat moss

  • rt_peasant
    Original Author
    14 years ago
    last modified: 9 years ago

    Just a quick update, I tilled the peat moss into my garden today. I've never felt soil so nice! It is soft and spongy, like crumbled angel food cake. I can't wait to get some seeds into it!

  • jonhughes
    14 years ago
    last modified: 9 years ago

    Hi RT,
    Make sure you follow Idaho's advice...put lots of mulch on it and keep it mulched,(leaf mold or compost etc etc) your soil will simply get better and better.

    Here is a link that might be useful: Awesome Soil

  • biggjoe
    14 years ago
    last modified: 9 years ago

    It's amazing all the different opinions you get when you ask a question here. I'm new to gardening but it seems like everyone has their way of planting and gardening and what works for one person might not work for someone else.

    Take for instance the question about the Peat Moss. I went to what is the largest and most popular nursery in our city and one of their gardening pro's(60+year old gentleman) told me how I can improve the soil for my garden. He told me that he's always mixed Peat Moss into his soil with some type of soil conditioner and/or manure. That he said is all you need. He even stressed, "NO FERTILIZER". Maybe the soil here in Indiana is very rich, I don't know, but I would tend to trust the suggestions of a guy who's been gardening for 40+ years and works in a garden nursery.

  • david52 Zone 6
    14 years ago
    last modified: 9 years ago

    I bought my place from some folks who were not all that concerned with amending garden soil, and it was pretty much brick. I tilled in Lord knows how much peat moss, call it 6" thick on every flower bed, the first few months I lived there and planted some perennials. By next spring, you couldn't find any trace of peat moss at all. But the flowers got off to a nice start, and are still doing well.

    As bpgreen says above, this is nearly broken down when you apply it, and you might check in a month if you can even find a trace of it in the soil.

    I think one could make an argument that when starting a lawn from seed, a mixture of peat moss and some composted manure as a readily available nutrient source could be made, tilled in 4" deep. Maybe too for perennial flower beds to get them off to a good start. As a mulch, it's silly, it just dries out and won't allow any moisture in, and then blows to Kansas.

    As my gardens expanded (I live on 3 acres) peat moss became cost-prohibitive. I now use leaves, grass clippings, horse manure, aspen and pine saw dust, and home made compost, all of which are free.

  • borderbarb
    14 years ago
    last modified: 9 years ago

    After 40 years of gardening, I bought my first bale of peat moss. .... due entirely to water restrictions forced on us by water shortage caused by over-population of a semi-arid region. I think best advice from above is to make sure the peat moss is throughtly wet/damp before incorporating in the soil. And to mulch all open soil to keep the pm moist. I've been digging a handful of wet/damp pm in the bottom of every planting hole ... in hopes of adding to the moisture rention of my soil, and mulch like mad!

    BTW - I notice from lurking in the vermiculture forum, that pm is often used as 'bedding' for worm bins. Since IMHO there is no single magic elixer to make good environment for plants ... judicious use of pm along with other ways to add OM to our soil, plus mulching AND a good herd of earth worms -- these comprise the elements needed for healthy soils/plants.

  • tishtoshnm Zone 6/NM
    14 years ago
    last modified: 9 years ago

    Your soil is likely very similar to what I have here in E. New Mexico. Ours is very alkaline clay. One of my favorite composts to work in is Acidified Cotton Bur. This is different than standard cotton bur and I purchase it from a nursery. The acid of course helps with the pH issues but I love the cotton bur because it is coarser and therefore a boon to the compacted clay. Good luck!

  • jolj
    12 years ago
    last modified: 9 years ago

    I have Sphagnum Moss in the swamp that is on the edge of my property. It grows in swamps in a lot of North America.
    It is not deep in my little wet spot, but it does grow.
    It is yellow green, looks like small conifer tips.
    Sorry no Pic's.

  • wayne_5 zone 6a Central Indiana
    12 years ago
    last modified: 9 years ago

    I have already posted on how well I love the 90% sphagnum peat moss with some black fines I get from a local bog that is much cheaper than the baled pm. It is an excellent soil conditioner for my clay loam. It never dries out here and just keeps giving.

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