Earth Juice makes a product call "Meta K" that works really well, the NPK is 0-0-10
So, there is no guess work about the K and it's easy to use.
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Hardwood ash runs about 5 to 10 (soluble) on average, but is very alkaline, and tends to push pH up. It must be used with caution.
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Hope this helps....
Keep it Real.....Organic......
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