Neutralized Wood ash with vinegar as the ultimate flower fert

[carnalrekt]

Hello All,

Wood ash is known as a good source of potash and other minerals but also needs to be used sparingly to to its high ph.

It occurred to me a while ago to neutralize it before use to avoid any issues.

However there is almost no info on the net about the usefulness of this, except for this little writeup i found on another forum :




"I thought I would share a simple solution to the use of wood ash as a fertilizer.

I found, like many, that wood ash+ water yields a very caustic solution, ph 9 in fact on my measurements. So I bought some cheap vinegar, and added it to quench the caustic solution.

The results have been remarkable, one trailing rose is producing nearly 2 kilos a week of dead heads, and requires nearly daily attention to remove the dead flowers."

"I have found that 1 litre of white wine vinegar per 2kg of wood ash is approximately correct. I use pH strips, and just bring it back to ~7ish, dilute with 150 litres of water. Stir. Allow 5-6hrs to settle. Stir again and use."

https://www.houzz.com/discussions/3146705/wood-ash-add-vinegar



Potassium, and calcium acetates are a created as a result of the acid base reaction and are both bio-available and easily taken up by plants.




I do believe this simple acid base reaction before using wood ash will improve the usability of it in the cannabis growing scene...though i might be wrong.

I am in the middle of my first organic indoor 100w microgrow and i do not have sufficient experience to tell the difference in yield. Nor the ability to do any serious testing at the moment.

What I am hoping to do though is find the upper limit of use of this vinaigrette So im looking for some feedback from some old hands....


How much do you think i should use? The recipe above roughly adds up to 1:50 vinaigrette to water ratio. Should i start here and work my way up in concentration?

How often should i use it? Every watering? or alternate?


What happens if i have some kind of nutrient or salt overload? Should i flush with water?

Would anybody else with a larger grow like to contribute to this train of thought and the knowledge pool by doing a side by side with a SOG or similar? Either swapping out their main potash source and or adding too it, playing around with concentration etc....


Thanks all

 

[St. Phatty]

just mix it with water.

when i make a nute mix, i start with about 3 gallons of human urine.

then use that to wash the wood ash, since it's all mixed in with char.

i remove the char and put in on some plant pot on the deck.

so at that point it's Nitrogen + Potassium.

Then add Chicken manure (2-2-2), and steer manure if i got it.

Then dilute all that, using 1 bucket of concentrate to make 4 buckets of diluted nutes.

Then all the fruit trees get about 1/2 gallon of the diluted water with the nutes.

Same for Cannabis except their soil has added Bone Meal (Phosphorus) and I splurge on the 1-9-1 Bat or Seabird Guano, just for the Cannabis, which also goes into the liquid nutes (more Phosphorus).

 

[igrowone]

subbing in, also have used wood ash sparingly

 

[voidpainter]

“If we add the ashes to water, the soluble potassium and sodium salts will dissolve while the insoluble silica and calcium carbonate will settle to the bottom. We can then drain off the water (containing the "good stuff") and throw the insoluble material away. To separate the chlorides from the soluble carbonates, we will exploit the greater solubility of the carbonates in hot water. We will bring the liquid to a boil and continue boiling until enough water boils away for an insoluble precipitate to form. This is very likely a mixture of sodium and potassium chloride. From this point, we will continue boiling until half of the remaining water is removed. At this point we can be reasonably certain that only the soluble carbonates remain in solution. We will carefully pour off the hot liquid into another container, leaving the solid material behind. As the liquid cools to room temperature, the less soluble sodium carbonate will precipitate leaving the more soluble potassium carbonate in solution. Finally, the remaining solution can be drained off and boiled to dryness, producing solid potassium carbonate.” - Cavemanchemistry

Just a fun bit of info.

Anyhow, I just use a heaping cup scattered around the base of plants when stretch ends, around mid August.

For indoor I use a heaping table spoon around the base. Might use more than a table spoon if in bigger containers.

 

[Cvh]

Nice. So simple and elegant.
Thank you for sharing.

 

[chilliwilli]

Hi folks
I use ash as a top dressing but after the watering. When the oxydes come in contact with the wet soil they will form hydroxides. You dont want this to happen in the soil. The hydroxides will react with the co2 of the air and form carbonates that are way less caustic than the oxyds. Never had any leaf burnig with that procedure but only used it twice with very low amount(~5tbsp per 90l pot)

Alternative you could mix the ashes with water in a seperate container and add this after its dryed again.

 

[carnalrekt]

Thanks for the replies folks. I see there are people using wood ash out there- either top dressing sparingly or probably diluting heavily... Im all for using urine along with as well.--but im pretty certain no one has tried the vinegar combo or posted about it if they have.

My goal is to find out what are the upper limits of vinaigrette that a plant can absorb. Can it even possibly replace guano or bloodnbone completely? I would wager yes ....Vinegar would theoretically allow you to push much harder on the wood ash without danger of ruining your soil ph. In the post in the link, the rose grower is using it on seedlings as well without issue.

Here is another thought : Wood ash would likely have plenty of trace minerals as well that MJ would likely appreciate. If the vinaigrette is prepared in advance, the neutralized wood ash might be mixed into the soil directly after siphoning of the liquid that is to be used when the plant is flowering. I might do this on my next grow.

Guano and blood/bone meal though not terribly expensive are extra purchase, while Vinegar/wood ash is usually lying around...

I have begun neutralizing some ash today...I added 900gm of vinegar to 300 gm of sifted hardwood ash. although it initially showed a neutral ph after some bubbling, 6 hrs later its still around 8-9 so I have added another 300gm vinegar , just the usual distilled white cooking vinegar. I Have found the original recipe's ratio doesn't work for me.

My plant has just started showing the first signs of budding. It doesn't need a watering at the moment but the next time it does i will try a 1:40 mix. next watering i might do 1:30 and see how it goes I will update on the results of my grow and final yield. Right now I am running a Deimos auto from freespore.es, but i plan to do further comparative testing on some photo clones a few months down the line and will post the results here as well.

 

[igrowone]

a point of interest from some googling
the ph of potassium acetate solution is 5.5
the ph of potassium nitrate solution is 6.2
of course this may not be apples to apples exactly, saturated solution at room temps?
in any event the acetate has a lower ph than the nitrate
that makes little sense since nitric acid is a far more acidic beast than acetic acid
but chemistry has many twists and turns