Friday 21-04-2023 - 14:46

Coffee grounds, the waste you throw away with no consideration, can make your garden happier in several ways, and in turn making you happier… and not just the happiness that the coffee gives you with more energy for weeding and pruning.  If you make your coffee daily or get yourself one or more cups from your university campus café, think about repurposing the grounds left behind from your coffee beans. You may have noticed your university campus cafe has started to put out bags of used coffee; you may be wondering about composting with coffee grounds, and these bags can be taken free of charge to support your composting needs.

Need some facts to encourage you to repurpose your coffee grounds for gardening? Are coffee grounds as fertilizer a good idea? How do coffee grounds get used for gardening? How do you use coffee grounds for gardening?

Coffee grounds can be a good source of nitrogen in your compost pile or when added directly to the soil in the garden. If added in fairly large amounts, they can raise the acidity level of the soil for acid-loving plants. Coffee grounds sprinkled over the ground around acid-loving plants serve as a mild acid fertilizer for them. Worms seem to love them, either in your garden or outdoor compost pile or in a vermicompost bin.

How to Use Coffee Grounds in Your Garden

Use Them as Compost

Using all those spent coffee grounds as compost is a very sensible choice. Just add them to the heap and let the compost bin do its job. Incidentally, composting is taking off in the coffee industry as well. Many pods are now designed with the view of being compost friendly. If you choose to drop coffee grounds in the compost bin, remember they qualify as green compost material. You may want to balance it with brown compost material.

Using Coffee as Fertiliser

Adding coffee grounds directly to the soil as a fertiliser can be a good option. Coffee grounds are rich in nutrients, especially nitrogen. They also have some amount of other nutrients like potassium and phosphorous. Overall, this means that adding coffee grounds to your garden can work well as a fertiliser. Coffee should be spread in a thin layer, rather than being clumped in one place. Spreading it as a thin layer not only spreads out the nutrients, but also reduces the chances of caffeine affecting one spot of the garden.

Feed Your Worms

Add coffee grounds to your worm bin every week or so. Worms love coffee grounds! Just do not add too many at once because the acidity could bother your worms. A cup or so of grounds per week for a small worm bin is perfect. In addition to using coffee grounds in your worm bin, earthworms in your soil will also be more attracted to your garden when you use them mixed with the soil as fertilizer.

Keep the Pests Away 

Create a slug and snail barrier. Coffee grounds are abrasive, so a barrier of grounds placed near slug-prone plants may just save them from these garden pests.  However, be warned that some researchers quibble with this advice and do not think it is effective. You may want to have a backup plan in mind if it doesn't work. Many cats dislike the smell of coffee grounds and may avoid using your garden as a litter box also if you mix coffee grounds into the soil.

Redhwan Al-Amri 
Events & Campaigns
(Swansea)