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obregon562

Ash (burned fire-wood) for composting?

obregon562
14 years ago

Hi guys,

Would it be safe for my plants to start dumping ash from my fireplace into my composting bin? Would it add any benefits to the soil? My only concern is that we used Duralogs to fuel the fires, and im not sure if they have any harmful chemicals.

Let me know, and thanks!

Frankie

Comments (19)

  • borderbarb
    14 years ago

    May I suggest reading some of the posts on a similar question: http://forums2.gardenweb.com/forums/load/soil/msg1217015819993.html?18

    I wonder about the Duralog ash, too. I'll bet someone on this thread will know.

  • Kimmsr
    14 years ago

    The manufactured logs (Duraflame is one) are made of sawdust and other agricultural waste (unidentified) and held together with some, non petroleum, wax. There are additives that aid the burning that, theoretically, are consumed by the combustion process. Cornell, and others that have researched composting, have found that the Calcium Carbonate in wood ash can have a detrimental affect on the bacteria that digest the material in your compost pile, although small quantities of wood ash may not be all that problematical.

  • scrapbone
    10 years ago

    It seems that the use of ash in composting should be done sparingly if at all, but what about the charred bits of wood that have not been completely turned to gray ash? I have been discarding the fluffy, light ash then crush up the jet black mostly burned pices into a mix of pea to grape sized pieces. Anyone know if there is benefit to soil or compost with this carbonized mix? Thanks

  • gardenlen
    10 years ago

    through burning old tree buttresses we got heaps of ash all went into the garden.

    len

    Here is a link that might be useful: lens garden page

  • Kimmsr
    10 years ago

    There are those that have looked at something called bio char and think that this material may help increase nutrient storage in soil. There are others that have looked at that research and found it flawed and the results did not support the conclusions.
    Keep in mind that forests, for eons, had chunks of burned wood left behind after a fire with no real harm done. Also keep in mind that charcoal is not a substitute for other organic matter in soil.

  • lazy_gardens
    10 years ago

    It depends entirely on what the soil analysis says.

    Around here it would be adding alkaline material to an alkaline soil ... BAD IDEA.

    Elsewhere, a light sprinkling of wood ash adds minerals and lowers* raises pH in a helpful manner.

    I would not put it in the compost because you will get clumps of highly alkaline ash and it's going to be hard to break them up when you turn the bins.

    EDITED: yes, it would RAISE the pH, not lower it.

    This post was edited by lazygardens on Fri, Dec 13, 13 at 16:17

  • lonmower
    10 years ago

    from Steve Soloman...

    "Wood ash from hardwoods is rich in potassium and contains significant amounts of calcium and other minerals. Ash from conifers may be similarly rich in potassium but contains little else. Wood ashes spread on the ground tend to lose their nutrients rapidly through leaching. If these nutrients are needed in your soil, then add the ash to your compost piles where it will become an unreachable part of the biomass that will be gradually released in the garden when the compost is used."

    Here is a link that might be useful: Soloman's Book on Composting (free online)

  • toxcrusadr
    10 years ago

    The composting process does neutralize things toward neutral pH, to some extent, but you do have to be careful with ash as its pH is very high. (I think lazygardens made a typo there, it will *raise* pH not lower it). If your soil pH is low, you can sprinkle it right on the ground. If you add it to compost, sparingly means a couple of cups per cubic yard of input materials. If the pH of the compost gets too high, it can throw off nitrogen as ammonia gas, which is not a good thing.

    I use the small charcoal bits as a soil amendment, I have heavy clay and the theory is they will help lighten it and improve drainage and aeration.

  • seysonn
    10 years ago

    I just wonder, why one would want to put wood ash in compost pile !!. ASH is already a finished product by itself, ready to be used. And I don't think it contains anything to contributr to composting.
    JMO

  • mikebotann
    10 years ago

    I exclusively heat my house with wood, and regularly spread the ash about the garden.
    When I loosely spread wood ash on dead grass it breaks down faster than where I don't put it. Shows me it helps composting.
    I treat my whole place as if it were a compost pile. Organic matter breaks down fairly fast in our climate here near Seattle.
    Mike

    Here is a link that might be useful: My garden

  • TheMasterGardener1
    10 years ago

    kimmsr said it. It is NO excuse for a healthy soil. Don't bother with the ash. Composting is one of those thing- if you have to think about it, don't add it.

    Gardeners say NOT to compost meat. Can you? Sure. But we want a clean and controlled compost. We want to know whats in it, and we want it to compost quick.

    Ash ups the ph and has sulfur in it. I 'think'sulfur is all it has, so whats the point?

  • toxcrusadr
    10 years ago

    No, wood ash also contains P, K, and a host of micronutrients like Fe, Mg, Mn, etc.

    I mainly do it to keep it out of the landfill, since my soil can handle the small pH hit, and I'd rather have those nutrients back in my soil than in the landfill.

  • seysonn
    10 years ago

    Most soils in the US are on the acid side. So wood ash with as big source of Potassium ,among other things, is a cures for acid soil. I have used it for years, instead of lime.

  • toxcrusadr
    10 years ago

    It is a good idea to have a soil test even on soils that are in 'maintenance' mode, every few years. I found my P and K were particularly high last year, after many years of compost additions to the garden. I need to focus on some other issues to get my plants to grow better, and cut back on compost and fertilizers that are high in P and K.

    The same situation could also happen with adding ash to soil annually. It has a lot more K than lime (which usually has essentially none), so in that respect it's not interchangeable with lime.

    This post was edited by toxcrusadr on Thu, Dec 19, 13 at 12:58

  • briergardener_gw
    9 years ago

    In place where I grew, ashes from wood stoves always ended up in gardens and people were growing great veggies in these gardens.

  • Kimmsr
    9 years ago

    Some people do advocate putting wood ash on, or in, the garden and maybe it could be of some value, but not the range of nutrients some suggest. Wood ash is about 25 percent Calcium Carbonate with less than 10 percent Potash and even less Phosphorus.
    The primary reason for using wood ash would be to quickly, and for a short time, raise a soils pH, if that is necessary. Wood ash in a compost pile does nothing, worthwhile, for the materials that are being composted.

    Here is a link that might be useful: wood ash nutrients

    This post was edited by kimmsr on Thu, Jan 22, 15 at 7:13

  • grubby_AZ Tucson Z9
    9 years ago

    Heh. So much blather running all over the place that the Original Post gets lost. "Would it be safe for my plants to start dumping ash from my fireplace into my composting bin?"

    Safe? Yes. As one highly reliable poster from GB has said: "if it has ever lived, pile it on" (or something like that...).

    "Would it add any benefits to the soil?"

    Yes, No, It depends. It WILL add stuff. You could wing it and judge the results over time as most people do, but that might be instant or it might be interminable. You need to know what's in the ash and you need to know what's in your soil.

    " My only concern is that we used Duralogs to fuel the fires, and im not sure if they have any harmful chemicals"

    Do you trust modern industry? I do not, but these logs seem to be cool, emissions-wise, sustainability-wise, and residue-wise.

    Forget all the bogus stuff. This is amending with lime at a chemical level of intensity and you don't yet know your general pH range. Since all gardening is local, do the numbers or you're just taking your chances. Nobody can do this but you.

  • armoured
    9 years ago

    On the OP's question about adding from fireplace to compost: I have done this with no ill effects (that I could see). BUT: the primary issue will not be whether it can be done in modest amounts, but how much ash you have. I partially heat with wood and there's no way my compost piles could handle all the ash. I generally spread the rest around the yard with no obvious issues if amounts are not excessive.

  • toxcrusadr
    9 years ago

    I figured out that if all the ash from my woodstove was spread on my suburban yard, it would amount to something like 1/16" per year, which is not very much. The trick is figuring out how to spread fine ash evenly, and I haven't got that figured out yet. Walking around shaking a fine screened kitchen strainer is kinda slow. :-]