Don’t Throw our those Coffee Grounds!
If you routinely toss your coffee grounds after your morning brew, you are not making use of your resources very effectively (one of the tenets of permaculture). Here are a few things you can do with those grounds instead of tossing them into the trash.
Put them into your compost pile with your other kitchen waste. Coffee grounds are a good source of nitrogen (about 1.5%). Adding them to your compost pile puts all those essential elements back into your garden.
If you notice that fungus is starting to grow on your compost pile, especially on the coffee grounds, you should add some wood ash or lime to balance out the pH. This fungus will consume all the available nitrogen, so adding more organic matter and working the coffee grounds into the soil will help keep the fungus at bay.
Use them as Mulch
Yes! You can use them as mulch or top dressing around your plants. You must be careful how much you use and how often because coffee grounds tend to be acidic and can raise your soil acidity. However, there is an upside to this.
Acidic soil loving plants will thrive when top-dressed with coffee grounds. Plants like blueberries, huckleberry, holly, azaleas, rhododendrons gardenias, camellias, and begonias all prefer acidic soil. Topdressing around them regularly will bring the soil pH down, and your plants will be much happier. West Texas soils have a notoriously high pH and using coffee grounds is a natural way to regulate the pH.
Using coffee grounds is good in your vegetable garden, as well. Plants like peppers, radishes, sweet potatoes, tomatoes, and rhubarb will appreciate an occasional treatment with coffee grounds.
If you are a hydrangea fan and have lamented that you can’t grow hydrangeas in West Texas, try starting a few and mulching them regularly with coffee grounds. If you can get them to bloom in our climate, the coffee grounds will turn them a brilliant blue.
When mulching with coffee grounds, put a layer about one-half inch thick around your plants. If you add more or get it too thick, the coffee grounds will mold, which can lower the pH of your soil too much.
Making Liquid Fertilizer
Coffee beans are rich in nitrogen, phosphorus, potassium, copper, and magnesium. Even used coffee grounds have a generous amount of these essential elements. It is easy to get them into your garden or landscape by making coffee grounds tea.
Put about a half-pound of used coffee grounds in a five-gallon plastic bucket, fill it with water (rainwater is best), stir and let it sit for at least 24 hours. Making coffee grounds tea is the same recipe you use for compost tea. You can double the effectiveness by adding about a half-pound of good compost to the bucket as well.
When the brew has steeped for at least 24 hours, the resulting liquid is your fertilizer. Use coffee grounds tea in several ways. You can pour it into your beds or containers as a drench. Don’t put so much that it flows out of the bottom of the container. That is just wasteful.
You can use it as a foliar spray. Spraying requires straining the liquid to remove any solid material. Straining the liquid prevents clogging your sprayer nozzle. I do this regularly in our garden. I mix about 2 cups of the liquid concentrate with a gallon of water. I also add a tablespoon of liquid dish soap to the water to act as a surfactant, helping the liquid spread out and cling to the leaves. I spray this mixture over all my plants, making sure I get the tops and undersides as well. Compost tea is the only liquid fertilizer that I use in my garden.
Used coffee grounds make a great substrate for growing oyster mushrooms. Most commercial growers use pasteurized straw as their substrate. The brewing process naturally pasteurizes your coffee grounds, making them a perfect material.
All you need is a container, some fresh coffee grounds, and a package of mushroom spawn to get started.
If you don’t make enough coffee grounds for your garden or landscape, visit your local coffee shop. Most of them toss all those grounds into the trash. Sometimes, just asking and providing a bucket for the grounds is all it takes to source a ready and plentiful supply of used coffee grounds.
Wherever your grounds come from, they are an awesome addition to your garden.
Links and Resources
For more information about organic gardening, lifestyles, and living, visit our website at West Texas Organic Gardening.
If you found the information here helpful, you might also find these articles on our website of interest.
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