Ashes in the garden

FWIW (as a chemistry teacher), ashes are mostly KOH. Potassium hydroxide (KOH) is extremely soluble in water (all compounds with potassium, a group 1 metal are). That being said, it's possible that with enough throughput of moisture any OH- that's at a harmful level will be diluted and/or washed deeper into the soil horizon: more easily in sandy/loamy soil (clay has less water permeability, hence clay pots, clay-bottom ponds etc). Considering the snow many of us have had, that water is going to help dissipate the concentrated KOH from ashes. I'd ditto what others have said to spreading thin: it's easier to dissolve a spoonful of sugar when it's spread out rather than in a lump in the bottom of the cup. In a perfect world we'd also add some bicarbonate salt of some kind since it buffers really nicely at near neutral pH. Don't use the baking soda though, the sodium ions can have toxicity as well: you'll keep chasing your tail there.

Well if you are in some areas of the country, there is a lot of Cesium-137 in the wood ash. I don't think Michigan got much radioactive fallout during the nuclear testing in the 50s.

tsquini said:

You have to be careful not to much too charcoal in the garden all at once. It has a very high ph, around 8. Charcoal/biochar will compete with the plants to absorb nutrients for the soil. The biochar will always win. I have a compost that I place all my ash and charcoal in. After a year I transfer it to the garden. After a year the ash and char has time to absorb all the nitrogen from the compost and do the garden good.

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a ph of 8 is no where near "very high" it's only 1 point higher than neutral. very high is 13+. I've never added ash to my garden, but probably should.... It's ringed with more than 10 bull pines 80+' feet tall. We (my wife and I) place the tomatoes closer to the pines.... they love it :D

DougA said:

Everything in moderation is OK. I assume that you did not burn pressure treated wood in your stove, which is a huge no-no, even worse to spread those ashes in the garden.

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any copper arsenicals left in the ash are going to be far less bad than the lead arsenate that was used for DECADES as a pesticide

each vegetable has it's own requirements... tomatoes like slightly acidic soil with a ph in the low 6's, which is why I put my tomatoes by the pines.... pine needles contain a large amount of tannic acid, so it works great for them.... for the rest of the plants I have to lime the crap out of the soil. My property is at the end of a 5 mile long gravel bar... and it's about 10' or so to ledge.

A Johnny's seed catalog will give you the soil requirements of anything you're going to put in the garden.

I put my ashes in the garden. I've heard you need to spread them out evenly and not dump it all in one spot. Dumping it all in one spot can cause salts to form, which can be bad.