A large bucket of ash – the result of cleaning out our wood stove – had me searching for ways to use wood ash. A byproduct of burning hardwood, wood ash is far more useful than I expected. It can be used to decrease soil acidity and sweeten smelly worm farms. Chooks love to bathe in it, and it can even be used to make soap.
What is wood ash?
Wood ash is the fine grey powder left behind after burning wood. Its composition varies but it typically contains lots of calcium carbonate – a compound that naturally occurs in limestone. It also contains potassium, magnesium and many trace minerals.
It's a useful frugal alternative to garden lime
Given its high calcium carbonate content, wood ash acts as a liming agent, raising soil pH levels and decreasing soil acidity. This makes it a frugal alternative to garden lime.
I'm now storing our wood ash in a lidded bucket and will use it throughout the year just as I would garden lime.
It should only be used in small amounts and when a decrease in soil acidity is desired.
Australian soils are typically acidic – so adding wood ash will make our soils more favourable for plants that like neutral to alkaline soil.
Wood ash is also a good source of potassium (promotes flowering), calcium (helps build strong cell walls) and numerous other useful nutrients.
Plants that are likely to appreciate a little wood ash include...
..lavender, citrus, flowering annuals and many vegetables such as tomatoes, peas, beans, spinach and garlic.
I’ll be tossing a handful of wood ash into each hole when I plant my tomatoes this spring. I’ll also be digging wood ash into my bean bed.
Wood ash shouldn't be used on plants that prefer acid soils such as..
...blueberries, strawberries, rhododendrons, camellias, azaleas, Australian native plants, potatoes or sweet potatoes.
When adding wood ash to your garden, mix it with compost or dig it into the soil to prevent it from blowing away.
Use it to sweeten compost bins and worm farms
Wood ash can also be added to smelly compost bins or worm farms to decrease acidity.
I've noticed worm farm and compost conditioners for sale. I’m guessing these are merely overpriced and over-packaged garden lime. Save yourself the money and instead sprinkle a handful of wood ash into your worm farm or compost bin now and then.
Use it as a dust bath for your chickens
Wood ash can also be used as a dust bath for chooks. Apparently they love it. Giving chickens a container of wood ash to dust-bathe in will help deter mites and lice.
A cat litter tray of wood ash would be a safe alternative to dust-bathing for urban chooks where there may be a risk of lead contamination in the soil.
Wood ash soap
I was surprised to learn wood ash can be used to make soap. Soaking ashes in water makes lye, which can be mixed with animal fat then boiled to produce soap. It doesn't sound very appealing – but this is how soap was made before we had palm oil and petrochemicals.
And finally, if you have smelly shoes, wrap a handful of wood ash in a piece of cloth and pop it into your shoe and apparently the smells will disappear.
My bucket of wood ash seems far more valuable than I ever could have imagined.
Originally published in the Newcastle Herald Monday 3rd August 2015.