Using Coffee Grounds in Your Garden

Over the years, there have been many pro and con messages circulated about the benefits (or not) of using coffee grounds in your garden. Oregon State University (OSU), a trustworthy source, has written an article on how to appropriately reap the benefits of this abundant resource!

According to OSU, spent coffee grounds (used in the correct amount) can be both a soil amendment or a compost ingredient. OSU also states that “even though coffee grounds provide minor amounts of potassium, phosphorus, calcium and magnesium and very minor amounts of iron, copper, manganese and zinc, these nutrients aren’t supplied in sufficient quantity to satisfy plant needs. Coffee grounds are best at improving soil. As the coffee grounds feed the soil microbes, microbial glues are released that promote good soil structure and improve drainage.”

One further benefit from this most popular drink: liquid coffee acts as an effective slug killer! OSU’s research shows that a coffee drench (1-part water to 2-parts of strongly brewed coffee) caused 100% of slugs to leave the treated soil and subsequently die of caffeine poisoning. A coffee solution (9-parts water to 1-part brewed coffee) can also be applied to foliage to reduce slug feeding (test this out first on a sample area).

The full article (including how to make a coffee soil drench) is linked, below…/used-appropriately…

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I’m already planning to test on slugs!