5 ways to use ashes in the garden – for composting, improving soil and more

What to do with ashes from a fire pit? Are BBQ ashes good for a garden? What can I do with pizza oven ash? These are all questions we've been asked recently – and it's no surprise. We all use BBQs, firepits, and pizza ovens, and the question of what to do with the ash has come up frequently. But did you know that the leftover ash can be put to good use in the garden? 

Ashes are full of surprising qualities that can boost your acidic soil, compost heat, and deter pests, among others – meaning that using ashes in the garden is the perfect way to limit waste and improve plant health. 

See: Backyard ideas – design ideas for your backyard, whatever its size or style

Here, experts reveal five ways to safely – and effectively – use leftover ashes in your garden – we can't quite believe its rich benefits. 

Using ashes in the garden – our top 5

Before we begin, Jon Butterworth at Arada Stoves (opens in new tab) reminds us to store our ash out of the elements to preserve its beneficial water-soluble minerals, that it could quickly lose in the rain. 

'Embers can stay hot for days, so make sure your wood ash is completely cool before using it around your gardens or home,' he adds. 

And a safety note from us – if you're going to empty your ashes into a container, make sure it's heat-proof, and not plastic.

1. Put ashes in compost to benefit plants

Perhaps the most significant but surprising advantage to recycling leftover ashes is in your compost heap. 

Yes, 'sprinkling layers of ashes in your compost heap will help break down the organic compounds and accelerate the composting process,' according to Co-Founder & Design Director at WoodenSTEEL (opens in new tab), Alex Waugh. He continues, sharing how ashes also 'help keep the smell down and control the number of insects it attracts, especially in warmer weather.'

See: Monty Don's warning about compost – heed his advice or risk attracting rats

'If you are using your ashes in your compost heap, always make sure that the wood you're burning does not contain any chemicals such as preservatives, paint or varnish. We recommend only utilizing dry seasoned firewood for our chimineas and fire pits,' Alex adds.

2. Is ash good for soil? Yes, it is

Ashes are a natural source of potassium and trace elements, and can correct acidic soils because they have a liming effect.

'Wood ash is approximately 70% calcium carbonate, and so it will offer the same result as lime, but at a quicker rate due to its particle size being much smaller,' Alex adds. 

See: Ways to use coffee grounds in the garden – extraordinary ways to boost your blooms

If your garden's soil is acidic or potassium-deficient, wood ash can help correct it – sprinkle it over the lawn and dig it into borders.

3. Use ashes in the garden to deter slugs and snails  

Alongside its horticultural benefits, we can use our wood ashes to ward off any pests. 

'Wood ashes can also be utilized to deter pests like slugs and snails and to repel ants. Sprinkle a small amount or ring around susceptible plants and reapply as rain can wash ash away and make it ineffective,' Alex shares. This is further emphasized by Jon, who also suggests stopping slugs and snails by 'making a circle of ash around plants they like to feast upon.' 

4.  Create a chicken dust bath with ashes

After taking care of slugs and snails, Jon shares how ash can be used as a chicken dust bath that controls other tiny pests; he suggests adding fine ashes to their dust bath, which 'helps to kill mites, fleas, and lice in much the same way that diatomaceous earthworks. Give your fowl the spa treatment with a few trowels of ash sprinkled around their dust bath area,' he adds.

It's worth noting, too, that a sprinkling of clean wood ash on chicken feed can be good for egg-laying chickens.

5. Use ashes in the garden to clean the BBQ

See: Best pizza ovens – our top picks to make the best at-home 'Za'

After the fun of a garden party draws to a close, there is one tedious task left to complete, and that is cleaning the BBQ. Like us, Jon doesn't particularly enjoy the clean-up, but he does have one tip that will make the process more seamless.

'Mix up a thick paste using ash and water and apply liberally to your grates and the inside of the BBQ. The ash and water will mix with the fats leftover from the cooking process and make a kind of natural soap, helping you clean up in no time,' Jon explains. 

We only wish we had known about this sooner.