Most of us know that coffee grounds are a byproduct of coffee brewing produced when coffee beans are ground and then hot water is filtered through them to produce that magical caffeine elixir loved world-round, coffee. However less of us may know this mandatory morning trash filler has a world of uses in gardening both indoors and out.
Coffee is high in nitrogen, magnesium and calcium while having a low pH of around 3 to 4.5. Due to this the ground remains of a cup of Joe can be used to make killer mulch, compost and fertilizer. Killer is the right word, the caffeine which is also present in coffee grounds may kill and will deter slug, snail and ant populations while attracting a more beneficial bug friend, the earth worm. The low pH will also help acid loving plants thrive, though unless applied in doses that would also harm plant leaves will not likely alter soil acidity much. The only known risk of recycling coffee grounds for gardening is mold, and mold can easily be avoided with proper use.
This guide on how to use coffee grounds in gardening will explain the many uses of coffee in gardening from how it’s done to why it’s done.
Coffee grounds can make a good mulch because they fertilize and repel unwanted insects while providing the benefits of mulch. Using coffee grounds as mulch is very simple.
Collect your left over grounds and mix them with chopped leaves. You want to mix the grounds with leaves because a straight layer of coffee grounds will dry, crust over and create a moisture barrier that will repel too much water from the plants. The risk of mold is also highest when using coffee grounds as mulch. Mixing with leaves will help this as well.
You can use just straight grounds if you wish, but if doing so should avoid using a thick layer and watch for mold. The mixture is then simply sprinkled over the dirt of the plant or garden.
Coffee grounds work best for mulching in gardens or plants that prefer more acidic soil as coffee is acidic. Try to avoid using coffee ground mulch on plants that like alkaline soil.
Coffee is probably most commonly used as fertilizer of all its uses. Coffee grounds will up nitrogen, magnesium and calcium content in the soil which is particularly beneficial in producing beautiful blooms and healthy fruits. The very presence of the coffee will also attract earth worms which is will aerate the soil, making it even healthier for plants.
To use coffee grounds as fertilizer you can either just drop a few teaspoons at the base of the plant every few times you water and/or mix it into the soil when planting or potting. The act of watering, whether you or the rain does it will help the nitrogen rich coffee brew right in the earth helping all the near by plants. You can actually even water plants with left over coffee to produce a similar effect, but be careful not to over due it.
Again, coffee may also affect the pH of your soil depending on how much and how often it is used. Luckily most plants do not mind slightly acidic soil but be sure you know the pH needs of the plants you are fertilizing.
Compost is produced by allowing materials to decompose naturally. Coffee grounds will be effectively neutralized in pH after being added to a compost pile making them safe to reap the nutritional, worm attracting and pest repelling perks of coffee ground fertilizing for alkaline plants.
Adding coffee grounds to your compost heap will also speed in the decomposition of the other elements in the pile. Avoid using a ratio of more than 25% grounds in your compost pile however as it may begin to tip the pH from neutral to acidic. If you are particularly worried about maintaining a neutral pH you can add a teaspoon of lime per five pounds of coffee added.
Coffee grounds let off an aroma that helps repel ants, cats, other animals and a wide variety of insects. Studies also show that the caffeine in coffee or tea even can kill slugs. However, to produce the concentration that would be needed to do so would also be harmful to plants. The concentration that is acquired by using coffee in any of the above forms will deter slugs and make them more likely to seek out other food sources.
In addition to being just an added perk of the many uses of coffee grounds in the garden you can also use it as a protective barrier. By creating a ring around your plants or garden using coffee grounds you will ensure the repellent effects. Many people suggest mixing the grounds with ground orange or citrus peels.
The only insect that seems to be particularly attracted rather than repelled by coffee grounds is earth worms. It is perhaps the organic material and nitrogen that draws them in. Earth worms will also neutralize coffee grounds as they feed on them, making their attraction to coffee ground filled compost heaps helpful in more ways than one.
As you can see what you may have thought was trash is actually black gold for your garden, put your addiction, or even someone else’s to use today.
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