Coffee is a wonderful drink. It can improve our cognitive performance, it tastes great, and it can give us the morning jolt we need to get us out the door and off to work. For many people, brewing a cup of fresh coffee is the first thing they do after dragging themselves out of bed in the morning. This leaves a crumbly glob of coffee grounds destined for the trash can. Those coffee grounds aren't necessarily useless though. In fact, there are many different uses for coffee grounds and in this article we'll be highlighting a major one: gardening. Coffee grounds are biodegradable and good for the soil, containing such essential minerals as copper, potassium, magnesium and phosphorus. In this case, one man's trash is a garden's treasure!
How to Use Coffee Grounds for Your Garden
It has beneficial pH levels
The acid in coffee is water-soluble, so much of it ends up in your morning brew and not in the coffee grounds. If you don't dry your coffee grounds out completely, they can be slightly acidic as well, with a nearly neutral pH of 6.5 to 6.8. It may not seem like much, but most soils in temperate climates in the Western hemisphere do well with a small boost in acidity.
It contains nitrogen
Aside from its mineral content and acidity levels, coffee grounds contain large amounts of nitrogen, an essential plant nutrient found in most commercial fertilizers. In coffee grounds however, the nitrogen is not immediately available to your garden plants. The uses of coffee grounds in gardening are far reaching. Coffee grounds release nitrogen into the surrounding earth as the microorganisms in the soil break them down, acting as a slow-releasing fertilizer that ultimately leaves your soil richer and healthier. Given how important soil quality is in growing plants, coffee grounds can easily tip the scale when it comes to producing stronger and healthier plants.
Coffee grounds may repel pests
Slugs, snails and other garden pests are a real annoyance for most gardeners. While some commercial pesticides can solve this problem, their long-term effects often do more harm than good. These commercial concoctions often destroy entire miniature ecosystems without regard for vital pollinators like honeybees and soil-aerators like earthworms. Caffeine is another reason why there are so many uses for coffee grounds in gardening. The caffeine in coffee grounds is a powerful deterrent for gastropods like snails and garden slugs, while being relatively benign to other insects and animals. Most cats hate coffee as well, which means you can use coffee grounds to keep Fluffy from using your camellia bed as a litter box. If deer are a problem in your area, the smell of coffee grounds can keep these big ruminants away as well.
Directly adding coffee grounds to your garden soil
You can add the coffee grounds directly into your garden soil by digging them six to eight inches into the earth. If you opt to do this, it would be a good idea to add a squeeze of lime juice and a little bit of nitrogen fertilizer to the soil as well. The lime juice will help neutralize the pH levels in the coffee grounds and feed the microorganisms in the soil that break them down. The more immediately available nitrogen in the fertilizer will nourish your plants while the digested grounds slowly enrich your soil.
You can also dry out your coffee grounds and spread them over the soil as mulch.
More uses for coffee grounds: improving compost
Coffee grounds make an excellent component for compost, speeding up the rate of decomposition while adding nutrients. This is one of the primary uses for coffee grounds in a gardening context. The high nitrogen content in coffee grounds makes them an ideal source, and the composting process allows that relatively inert nitrogen to become readily available once the composting process is under way. You can mix them directly into your compost pile, putting about three parts more carbon (such as grass clippings, dried leaves or even shredded coffee filters and scrap paper) into the mix to keep the volume and decomposition even.
Where can you find free coffee grounds?
If you or the members of your household do not consume much coffee at home, don't worry. Many coffee shops are happy to part with their used coffee grounds for free. Depending on where you live, some areas have a local online network or directory where gardening enthusiasts can connect with these establishments. Usually, all you need to do is ask.