Those fortunate enough to enjoy the warmth and comfort of a fireplace or wood stove know this wonderful benefit comes with a drawback. The drawback is after the wood burns it becomes ash and must be disposed of. Read further for a way to benefit from all that ash.
Wood ash is highly alkaline. Alkaline means, using the pH scale of 0 to 14 which measures hydrogen ions in solution, the number is above 7. Alkaline is a term used interchangeably with the term basic. On this scale 7 is neutral. Plants such as blueberries, rhododendrons and azaleas prefer slightly acidic soils but most prefer neutral to alkaline soil which makes wood ash a great way to enhance and condition the soil, rather than purchasing commercial fertilizer or lime.
Lime, calcium carbonate, is used to neutralize the acidity of soil. A soil test using small amounts of soil from several places in the garden, yard or pasture are blended and tested for pH and nutrient levels. From this sample a guideline for adding lime is given. Ash amounts can be figured by multiplying the recommended lime amount by 1.5 to determine the amount of wood ash by weight needed for direct application.
A rough estimate to apply ash directly to soil is one half cup to a 3 by 3 foot surface area. The ash remaining after burning the wood contains potash also known as potassium carbonate and trace minerals. During burning, nitrogen and sulfur are given off as gases but calcium, potassium, magnesium, along with trace minerals such as copper remain.
All wood is not equal in ash produced per pound of wood burned. Hardwoods like oak can yield 3 times the ash per pound and 5 times the nutrients per cord than softwoods such as fir trees Apply ash directly as a conditioning agent or fertilizer at a rate of one half to one pound per year per shrub or bush. Piles of lumps of ash mean high salt level and are harmful. 10 to 15 pound ash per 1000 square feet helps keep lawns healthy. I have a large yard and I spread the ash directly from the ash bucket, just be sure the wind is at your back. Although I do recommend following guides given if a more uniform dispersal is desired or if you will be embarrassed if the yard has some greener spots than others.
Some people dispose of ash in the trash bin but you don’t have to. Here is a more eco-friendly method of ash disposal. Wood ash can be put in the garden compost bins just be sure to mix thoroughly and turn weekly. An added bonus of these ashes is weed control. The alkalinity kills weeds. Unfortunately too much ash also kills seeds so be sure to allow at least two weeks before planting seeds after spreading compost in the garden if it contains wood ash. If you want to put the ash in garden composting bins, sprinkling in layers is important.
When handling ash directly wearing gloves is best because the ash can be as alkaline as bleach and very fine so you might want to wear a mask. Another method of addition is to make a scooped out place in the layer and put the small amount of ash in that hole then be sure to mix all contents completely. It works out to be about one cup to each square foot of compost being made.
I enjoy a fireplace throughout the fall and winter months. Wood burning creates an abundance of ash which can be disposed of using an eco-friendly method of direct addition to the soil or in garden composting bins or a composting tumbler rather than in the trash bin.