Using wood ash in the garden - balancing ph.

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The best way to know how much to use is by monitoring the soil pH yearly. Get a soil pH test reading yearly. You can do that yourself with a pocket pH meter or have a soil lab do it for you. Do you know how to test the pH of your soil?
I test the soil regularly for ph value and it's consistently 6.7 no matter what we do to it. So untouched clay is the same as beds that have been mulched with compost for years.
 
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If you add wood ash without a soil test you can run into problems with potassium lock out. Always get a soil test from the soil lab before adding anything to the garden.
Oh really. I've been living here over 25 years and I've never had a soil test done. My plants will tell me if there is something wrong. Like any supplements moderation is the key. I use ashes yearly but only a dusting enough to just cover the soil. Along with my other yearly applications of compost, leaf mold, peat moss, manure, bone meal, alfalfa pellets and gypsum, not to mention the different ACTs I brew up, my ph remains neutral to slightly acidic according to my ph meter.
I don't know if you watched that video but Nate is diluting ashes down to an 80:1 solution, certainly not an issue when it comes to raising ph too much. Again, moderation is the key.
 
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I have a slow combustion heater plus two big bonfires in the back paddock. I also have seven citrus trees that drop a lot of windfall fruit. The fruit and ash are dropped on the compost and although it was tested alkaline once it is fairly neutral normally. The ash is a very welcome form of potash. Legumes, brassicas and onions all prefer a slightly alkaline soil - I think?
 
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If you don't have a pH problem then that's ok for you. However, giving advice to others without knowing their soil chemistry is irresponsible. Adding wood ash can be toxic in someone else's garden. No disrespect to anyone, but recommending any special amendment or fertilizer without knowing the soil chemistry is inappropriate and reckless.
 
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To be fair, my opening post made it very clear that I was aware of the situation re ph levels, and of the fact that too much can effectively become a weed killer. So he was responding safe in the knowledge that I was aware of the dangers.

The nutrients in woodash are going to be beneficial to most soils. It's such a shame to waste them. Here's a typical nutrient breakdown:

When we're taking plants from our gardens we're slowly but surely stripping nutrients AND we're slowly turning it more acidic over time.

Someone mentioned in another thread that in a vegetable garden where you're harvesting your crops your soil will gradually become more acidic over time. The reason being, most plant matter is alkaline - if you don't let it rot down into the beds things will slide towards the acid level. Presumably this also applies when cutting grass and collecting the clippings and removing them?

Does anyone see any downsides in mixing the woodash with sulpher powder for beds where you're concerned about raising the ph level? I'd have thought that way you get the boost to nutrients without unwanted changes to ph level.

I know in traditional gardening soil testing is important, but interestingly, in the no dig approach I follow, the experienced guys say you don't need to worry about nutrients - as long as you build up the soil life/bacteria all of your plants will be fine. That's the approach I follow, but just as I wouldn't discard grass clippings, kitchen scraps and brown and green plant matter from the garden - I don't want to discard all that nutritious wood ash.

Composting is another contentious area, with some saying you need to mix balanced amounts of various plants. Yet others say just throw it all in - it'll take care of itself. But I'd have thought the more diverse and mineral rich matter is going in the better your compost and therefore your garden beds?
 
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RHS say 50 - 70 g of woodash per square meter.

I totally miscalculated my garden size earlier when I said it was 40 square meters (what an idiot). It's 20 meters wide, and 50 m long at the back with another 10 meters at the front. So that's 180 meters square.

Based upon RHS top recommendation I could safely use 7 x 180 = 1260 grams.

According to Google, 1260 grams in litres is 1.26 litres.

I would guess that over the season I produce 2 x 5 gallon bucket fulls. Now you need to seive it to get the big lumps out, but I expect that would bring it down to about 2.5 gallons.

So it would seem I really can only use a tiny proportion of the ash in the garden. Which seems such a waste.
 
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If you don't have a pH problem then that's ok for you. However, giving advice to others without knowing their soil chemistry is irresponsible. Adding wood ash can be toxic in someone else's garden. No disrespect to anyone, but recommending any special amendment or fertilizer without knowing the soil chemistry is inappropriate and reckless.
I test the pH of my soil and compost. It's not possible to know everyone's soil chemistry.
Slash and burn works and has for thousands of years. The heaped ash on the old bonfire sites is a problem unless removed and/or distributed. Spread thinly and mixed with acidic wastes like citrus windfall fruit, and urine it is not only harmless but very beneficial. Check the pH of your soil and compost before planting because most plants prefer slightly acid soil and wood ash is very alkaline.
Also ensure that compost is built in layers with wood ash being only a thin layer every tenth layer. Given the amount of weeds, straw, lawn clippings and manures that totally overwhelm the less then 0.1% ash component should ensure your compost remains the most value commodity in your garden.
 
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I should add that 'grape marc' is an acidic additive worthwhile considering if your compost pile should test alkaline. This is useful information if you live in a wine region where the 'marc' is the grape skins left over from crushing. It is available from landscape supply stores and, in my opinion, is better than adding the chemical Sulphur.
 
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If you don't have a pH problem then that's ok for you. However, giving advice to others without knowing their soil chemistry is irresponsible. Adding wood ash can be toxic in someone else's garden. No disrespect to anyone, but recommending any special amendment or fertilizer without knowing the soil chemistry is inappropriate and reckless.
So I'm wondering if you would say the same thing to anyone suggesting to use peat moss as a soil amendment because it's somewhat acidic, somehow I doubt it. Again, I made it quite clear that I was only using a light dusting of ashes. Maybe you missed that. For you to suggest they can be toxic would be like assuming pounds of it are being suggested to add to soils. As Susan rightly pointed out, they are an excellent source of many nutrients, minerals and trace elements that is totally natural and has been used as a soil supplement for hundreds of years, long before soils test came about. So I guess that also means you totally disagree with what Nate has posted in his video? I suggest you watch more of his videos to see where he's coming from as an organic gardener. Wood ashes are also recommended as an excellent barrier for pest control in the garden, specially for soft bodied insects like snail and slugs, both of which can be serious pests that cause a lot a damage to garden plants. But I guess that would also be a big no for you right? Better to use store bought chemicals?
I also guess you missed where I pointed out all the other amendments I add to my garden soil, all that organic matter goes a long way to stabilizing soil ph and most gardeners are well aware of the benefits of yearly additions of organic materials to their soils.
Finally, I was responding to a thread specifically asking about the use of wood ashes, so I gave her my opinion based on research as well as my experience using them for years in my gardens as along with the caveat to moderate the use of them. Nothing wrong with that as far as I'm concerned, isn't that what this forum is for?
Cheers
 
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When I was a teenager we took a bunch of Dad's sixth formers on a field trip to a fruit farm each year. One of the things we did was to put four stakes around a large bonfire site and dad made a frame that fitted over it with nails so you could string it into two inch squares and each year we recorded what grew. First year was mostly odd bits of lichen and moss, by the second year there were a lot of nettles, and so on, each year changing as the rain washed the ash, until finally it came back to the surrounding grass. That was a big heap of ash, several inches thick, a reasonable dressing will not change things much, and they will revert to the norm quite quickly.

Interestingly we did something similar with a square of chestnut coppice, mapping the plants as it grew from lots of grasses, foxgloves and various wild flowers the first year when it was at ground level to honey suckle and bramble when they were eight year old coppice standin ten or twelve feet high and casting lots of shade.
 
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So I'm wondering if you would say the same thing to anyone suggesting to use peat moss as a soil amendment because it's somewhat acidic, somehow I doubt it. Again, I made it quite clear that I was only using a light dusting of ashes. Maybe you missed that. For you to suggest they can be toxic would be like assuming pounds of it are being suggested to add to soils. As Susan rightly pointed out, they are an excellent source of many nutrients, minerals and trace elements that is totally natural and has been used as a soil supplement for hundreds of years, long before soils test came about. So I guess that also means you totally disagree with what Nate has posted in his video? I suggest you watch more of his videos to see where he's coming from as an organic gardener. Wood ashes are also recommended as an excellent barrier for pest control in the garden, specially for soft bodied insects like snail and slugs, both of which can be serious pests that cause a lot a damage to garden plants. But I guess that would also be a big no for you right? Better to use store bought chemicals?
I also guess you missed where I pointed out all the other amendments I add to my garden soil, all that organic matter goes a long way to stabilizing soil ph and most gardeners are well aware of the benefits of yearly additions of organic materials to their soils.
Finally, I was responding to a thread specifically asking about the use of wood ashes, so I gave her my opinion based on research as well as my experience using them for years in my gardens as along with the caveat to moderate the use of them. Nothing wrong with that as far as I'm concerned, isn't that what this forum is for?
Cheers
I would never recommend putting peat moss in acidic soil or recommend using it without a soil test. I don't make soil recommendations without knowing what's in the soil. Why? Because each soil is different and can be different when it comes to soil porosity.
 
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So I'm wondering if you would say the same thing to anyone suggesting to use peat moss as a soil amendment because it's somewhat acidic, somehow I doubt it. Again, I made it quite clear that I was only using a light dusting of ashes. Maybe you missed that. For you to suggest they can be toxic would be like assuming pounds of it are being suggested to add to soils. As Susan rightly pointed out, they are an excellent source of many nutrients, minerals and trace elements that is totally natural and has been used as a soil supplement for hundreds of years, long before soils test came about. So I guess that also means you totally disagree with what Nate has posted in his video? I suggest you watch more of his videos to see where he's coming from as an organic gardener. Wood ashes are also recommended as an excellent barrier for pest control in the garden, specially for soft bodied insects like snail and slugs, both of which can be serious pests that cause a lot a damage to garden plants. But I guess that would also be a big no for you right? Better to use store bought chemicals?
I also guess you missed where I pointed out all the other amendments I add to my garden soil, all that organic matter goes a long way to stabilizing soil ph and most gardeners are well aware of the benefits of yearly additions of organic materials to their soils.
Finally, I was responding to a thread specifically asking about the use of wood ashes, so I gave her my opinion based on research as well as my experience using them for years in my gardens as along with the caveat to moderate the use of them. Nothing wrong with that as far as I'm concerned, isn't that what this forum is for?
Cheers
Nothing wrong with it in your soil, however, if I didn't know better and did what you recommended for my soil, I would have a lot of problems. My soil pH is between 7.8 to 8.8, and adding wood ash would have catastrophic results. The existing alkalinity of the soil pH would be the main reason not to use it. If one's soil pH is above 7.5 putting wood ash on the soil can lock up macro and micro nutrients.
 
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Nothing wrong with it in your soil, however, if I didn't know better and did what you recommended for my soil, I would have a lot of problems. My soil pH is between 7.8 to 8.8, and adding wood ash would have catastrophic results. The existing alkalinity of the soil pH would be the main reason not to use it. If one's soil pH is above 7.5 putting wood ash on the soil can lock up macro and micro nutrients.
There are so many different approaches to gardening and unless you know what approach someone is following advice given can be catastrophic. We all need to do our own research and checking before blindly listening to 'bloke on 'tinternet'! I never trust anyone online. Ever. I always make my own decisions ultimately. What I value is the brainstorming of people freely sharing their thoughts and experiences.

I follow no dig. So whenever anyone talks about digging in this, that and the other I take responsibility for knowing when to ignore advice - their advice would be VERY bad for me. People don't test soil as a rule in the no-dig community. The whole approach is differrent - you don't need to know what the exact break down of your soil is because the prescriptiion is ALWAYS the same (I test mine out of curiosity rather than to work out what to put in it). A 1 inch layer of compost is applied to the soild every December - nothing more added.

The no-dig 'gurus' I follow don't sweat over what goes into their compost. They use what they have access to; manure, mushroom compost, coffee grounds, hedge trimmings, garden waste, kitchen waste. The materials I add to my compost heap vary in acidity and nutrients. As a rule, you just toss it all in and don't worry about it. I have access to as much cow manure as I want - that's acidic. So that would counter the high ph of the woodash. So how much manure vs how much woodash? And then you start wondering about the other nutrients in the woodash....before you know it you're trying to create a recipe for your compost heap. Yet most people will tell you - don't sweat it - if it was ever alive shove it in the compost heap. If you're afraid of attracting rats keep animal matter out.

So - why this feeling that woodash is different? (I'm not saying it's NOT different - I'm wanting to understand why we have to worry about woodash quantities but not acidic peat, manure etc). How much seaweed in my compost is too much? (I have access to all I can use). Should a warning be attached to advice to add pine needles or oak leaves to a compost heap (due to them being acidic).

Maybe the issue with wood ash is it's VERY concentrated. The nutrients distilled from 3 cubic meters of wood each year (in my case)?
 

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I follow no dig. So whenever anyone talks about digging in this, that and the other I take responsibility for knowing when to ignore advice - their advice would be VERY bad for me. People don't test soil as a rule in the no-dig community. The whole approach is differrent - you don't need to know what the exact break down of your soil is because the prescriptiion is ALWAYS the same (I test mine out of curiosity rather than to work out what to put in it). A 1 inch layer of compost is applied to the soild every December - nothing more added.

Ok, I have to check this out. I'll set up two rows side by side 10 ft in length. On one row I will do nothing but let the weeds go, do dig. Then at the appropriate time (when the companion row is ready for planting) lay down a layer of cardboard. Then put 1 inch of my best compost on top of that, then plant. Nothing added during growing, and no digging or weeding. Does that fairly represent no dig?


On the other row, I will do my normal soil prep which includes multiple chop and drop cycles with cow peas, a green manure crop turned under with tiller, and then 4-6 inches of composted cow manure tilled into the soil. At that point, that section will be planted in the same identical plants as the no dig row. This row will have all weeds removed during growth.

Production will be measured and compared. No soil tests. Does that sound fair? Any suggested modifications to the no dig row?
 
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Nothing wrong with it in your soil, however, if I didn't know better and did what you recommended for my soil, I would have a lot of problems. My soil pH is between 7.8 to 8.8, and adding wood ash would have catastrophic results. The existing alkalinity of the soil pH would be the main reason not to use it. If one's soil pH is above 7.5 putting wood ash on the soil can lock up macro and micro nutrients.
I totally agree there of course. I would expect most gardeners would have some sort of an idea of what type of soil they have. What I don't understand is how your soil could be that alkaline unless it's all native soil, in which case why would you not add supplements like sulfur to make your soil more neutral. Like, what can you even grow in soils with that high ph?
I bought my rocky treed acre back in '96 in mixed farmland and forests. We grow rocks real good here in Lanark and there isn't a lot of soil to work with. After breaking numerous shovels I finally got a large pinch bar after I figured out that the best way to dig holes for flower garden beds was to find the bigger rocks and remove them. My vegetable gardens are all raised beds as I had no other choice on the one good flat area I had to use that had enough sun. Saying that, over the years I've had three truck loads of soil and triple mix brought in to use as the base for all my beds and all the rest is supplemented with many wheelbarrows full of my made up soil mix consisting of bagged black earth, manure, and peat moss with perlite and some lime added. So basically all my gardens are mostly filled with soil that I added and then supplement with more bagged products along with my own compost and leaf mold as I have unlimited supplies of leaves. So with my soils mostly neutral ph and my yearly suplements I have zero issues adding the light dosages of wood ashes I use each year. My gravel driveway gets much more added each year in the winter when it gets icy from rain or freezing rain and I always carry a pail of ashes in my vehicle in case I or someone else has issues resulting from icy roads. Nothing works better on ice and seeing as I heat with wood I have lots of clean ashes available. Let me tell you that the weeds and grass sure don't have a problem growing in my driveway even with much heavier use of ashes.
Cheers
 

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