Welcome! Log In Create A New Account


Wood ashes

Posted by Zea Sonnabend 
Wood ashes
February 22, 2018 09:05AM
Someone gave me a rather large amount of wood ashes from burning their prunings. I want to use them since they are high in minerals but am not sure of the best way to go about it. I don't want to put them in the compost pile because it will cause nitrogen volatilizations. Should I worry about burning young trees if I top dress?

Fruitilicious Farm
Zone 9b in California
Re: Wood ashes
March 28, 2018 04:51PM
Yep. My soil was low in K, and I figured this would be a good way to increase it. It did. But at the same time it increased the pH to its current 8.2, (and we have acid soils here in NS). I am not putting any more on for now, and hoping that with the continued application of organic materials, the organic acids will eventually neutralize the excessive alkalinity.
So, yes, this is a long-established practice, which makes eminent sense. But you do also need to watch the effect on pH.
And, one caution: make sure you know what the ash is from. The ash left in the bottom of your wood stove is good. The soot left in the smoke pipe and chimney is VERY BAD. It contains all the heavy metals, aromatic hydrocarbons, and toxic stuff that you do not want in your soil. (I hadn't thought about it until now, but this actually might constitute a means of de-toxifying land - grow woody materials on it to trap the things like the heavy metals, then burn this to vaporize the toxins, which then condense in the chimney, and remove the concentrated toxins from the chimney for disposal.)

Broomholm Orchard
Zone 5b in Nova Scotia
Re: Wood ashes
March 28, 2018 07:14PM
I would put wood ash on sparingly and I have found that top dressing with pure wood ash makes for a tough environment in that top layer, pH issues, hard for seeds to germinate in cover crops and poor drainage/aeration overall. Mixing the ash into the soil would be the best option, perhaps in pockets or in a banding method vs total coverage. Wood ash has its place, but a little is helpful and too much is a nuisance with other unintended issues it creates.

Does your most recent soil testing indicate deficiencies you think can be addressed with the wood ash?

General rule of thumb would be to not use wood ash at all if your pH is at 6.5 or above.

Gopher Hill Apples
Zone 8 in California
Re: Wood ashes
September 03, 2021 05:29AM
An older thread but thought I'd chime in just to say I killed a two year old apple tree and a lilac bush with a couple shovel fulls of good wood ash. It's potent stuff.

Nat Bouman
Growing cider varieties in Zone 5b
On B.118 at 18X24
Susquehanna County, Pennsylvania
Re: Wood ashes
September 15, 2021 12:28AM
Eek! And here I came to this post with this question: We recently cleaned out our ash pit, not done since Biblical times, it seems, and came up with about ~260 lbs. of hard wood ash. I looked outside, and thought "Well the orchard is pretty big (for us - 3/4 acre) -- maybe that is a good place to spread it?" Fortunately, it seems, I more a ruminator than a doer, b/c I'd only thought about it so far. From your posts, it seems like this would be a bad idea (esp. w/o any application rate guidelines, which I haven't generally found online).

So what can I do with this stuff? I would hate to waste it, as there are a lot of great macros and micros in there, I think.

(Let's assume that I don't want to open a soap factory, nor kill a whole pasture's worth of weeds.)

Zone 7a in West-Central MD
Sorry, only registered users may post in this forum.

Click here to login