Coffee grounds are high in nitrogen, and make an excellent fertiliser for fast-growing vegetables. They also contain calcium, magnesium and potassium and can be lightly raked into the soil, or added to water and used as a soluble plant food. They are particularly good to use with plants that prefer slightly acidic conditions such as blueberries. In the general garden, spread small amounts in each application and avoid plants that don’t like acidity.
Coffee grounds may also help reduce damage from slugs and snails. Apparently they are repelled by the grounds and if the caffeine is absorbed through their skin it has fatal results. We’ll do a post reporting on our experience later in the year. Some people go even further and mix up a special batch of strong coffee for use as a foliar spray to protect plants. There would have to be a lot of plant damage for us to give up our cup of precious Yarra Coffee to use it as a spray. We’ll probably stick to using the coffee grounds in the garden after drinking the coffee ourselves. Perhaps we are too addicted?Like humans, worms also like coffee, and it promotes worm activity in both the compost heap and in the garden. As worms have no teeth they need to grind their food up, and use the coarse grounds as “grinding stones” in their gut.
A final benefit of coffee grounds is you get one last whiff of that tantalising aroma whilst you work in the garden. Unfortunately it doesn’t last all that long, before the coffee starts to break down.
