Been drinking more coffee from home during isolation? And wondering what to do with all that ground coffee waste?
Coffee can be reused as organic waste, instead of just chucking it into the garbage. But can it be used on your lawn? Unfortunately, the short answer is no – not directly anyway. But you can certainly use ground coffee waste in your compost to be indirectly used on your garden and lawn areas.
In today’s blog we explain why and how, and also discuss other organic waste products that can be added to your compost brew to keep it out of landfill.
The main reason some would assume coffee might be good for your lawn, is that it can provide organic material, including nitrogen and phosphorous. These things are great for nutrient poor lawns and lawns on clay or sandy soil. However, coffee grounds still contain some residual caffeine, which can cause harm to the micro fauna in your soil, and that’s why it is not recommended to apply coffee waste directly to your lawn.
Coffee grounds can also contribute to better aeration and drainage, which leads to a healthier lawn, but unfortunately the caffeine is just too damaging.
However, you can still keep your coffee waste out of the bin by adding it to your compost, where it can indirectly benefit the health of your soil.
Added to well-aged compost material, coffee grounds will contribute towards creating a fantastic top-dressing product for your lawn that will provide organic nutrients and moisture. This organic boost will supply key ingredients your lawn needs to stay healthy and create a beneficial soil environment for microbial activity… now that’s a win for coffee drinkers and lawn lovers!
Compost for top dressing will also improve the ability for your soil to hold moisture, which is super important for drought proofing your lawn. And let’s not forget that by composting your coffee grounds at home, you will keep them out of landfill and help our environment – another huge win!
How much coffee is too much?
Worried that too much used coffee grounds might affect the pH of your soil?
Like with any organic waste product you add to your compost, be mindful of ratios. Provided used coffee grounds are composted and make up less than 20% of total compost volume, they will not lower the pH of your soil making it acidic. The pH of the compost may show varying results and not be stable initially, in some cases even becoming alkaline.
But once the compost material is added to the garden soil, any acidity that was initially detected will soon decrease, leaving a pH around 6.5, which is the perfect for growing a healthy lawn.
Don’t have a compost at your place?
Here’s a quick rundown of what you need to know to get started:
Green and Brown Waste
A good layered compost, which can be placed in an old bin or purpose built into an unused corner of your garden, will have a combination of both green waste products and brown waste products.
Green waste (the nitrogen) can include fresh plant waste, grass, vegetable scraps, and coffee grounds… items generally high in nitrogen.
Brown waste (the carbon) can include dried or aged plant material such as dead leaves, newspaper, straw, wood shavings and cardboard. These items add carbon to your compost.
A good combination of both is ideal, with a higher amount of brown material to ensure your pile doesn’t get too wet and smelly. On the flipside, if it’s too dry, then more green waste is required.
What can I compost?
Banana peels, vegetable scraps and spoiled food waste from the kitchen are your most common compostable household items, but there is also a list of other lesser-known items that can be added, including:
- Hair - pet hair or human hair from a hairbrush can all go in as it contains nitrogen which helps the decomposition process. Spread the hair throughout the green items in your compost to help it break down quicker.
- Beer - we don’t advocate for wasting too much beer of course, however beer can be added to your compost pile as it helps to speed up the composting process. Beer is biodegradable and the yeast it contains will also feed microbes in the soil.
- Tea Bags are great because they help increase the speed at which your compost decomposes. However, make sure your tea bags are compostable as some contain polypropylene and won’t decompose properly. The organic matter from the tea leaves also provides moisture which promotes earthworms.
- Eggshells - when tilled into the soil, ground eggshells provide your plants with calcium. Although nitrogen, phosphorus, and potassium are vital for healthy growth, calcium is also essential for building healthy ‘bones’ (aka: the cell walls of a plant). It’s important the eggshells are finely ground as they won’t decompose well otherwise.
- Fireplace ashes - green waste breaking down can create an acidic environment and wood ash from your fireplace is more alkaline. Therefore, ashes from your fireplace can provide a neutralising effect on your compost pile. Ashes also provide nutrients in the form of lime and potassium, which can improve soil health.
Finally, how will you know when your compost is ready to use for top dressing your lawn? You’ll know when your compost has broken down and is ready to use when it becomes mostly soil-like in appearance and doesn’t have an unpleasant odour.
For more information on creating and maintaining your compost visit your local nursery or the Gardening Australia website here.
Prefer takeaway coffee?
Or, if grinding beans and preparing your own coffee from home sounds too onerous, there's always the option of take away from your favourite barista. Many local coffee shops are once again providing takeaway options of the good stuff to help us through the day. And... you could even ask for their coffee ground waste to add to your compost at home - another win for everyone!