Wood Ash

Asked February 22, 2015, 6:14 PM EST

I burned wood in my garden. Should I remove the ash or work it in the soil?

Outside United States

1 Response

I can't tell where you are writing from but in general they are okay. Here is an answer from William Sherrer of Bonnie Plants:
Wood ashes from the fireplace or wood stove may be used to supply both calcium and potassium to soil. The pH level of soil is measured on a scale of 0 to 14, with 7.0 being neutral. Target pH for growing a garden is 6.5 (slightly acidic). Wood ash works best if the soil pH level is somewhat acidic, below 6.5. Wood ash is high in calcium content, with the effect of raising soil pH. When wood ash is used at pH levels above 6.5, interference with plant growth may occur as the alkalinity level of the soil increases. The easy answer is yes, it can be good for the garden, if the garden needs it. If your soil is not acidic, the ashes can raise the pH too high. You can get a soil test kit from your local county extension office to determine soil pH and any soil amendments you might need. Here's a link from the Oregon State University Extension Service on Wood ash.