When you’re sipping your favorite cup of delicious coffee (whether you had some brewed at home or had ordered a cup from your favorite coffee shop), did you ever wonder where these things go afterward? Well, turns out coffee grounds can still be quite useful. Besides having to use it as part of your skin and hair regimen or as a soil and garden supplement, you can also use these as food for your compost worms.
If you’ve been wondering if worms like coffee grounds, the answer may surprise you. There are actually a number of ways that your worm farm can benefit from a few grinds of used coffee grounds. Read on to learn how these organisms react to the presence of this interesting organic fertilizer!
Coffee grounds can be a useful addition to a worm bin, providing nutrients and grit that benefits worms However, too much coffee can also cause problems that need to be managed properly. Used in moderation and balanced with carbon-rich materials, coffee grounds can improve vermicomposting results.
Why Worms are Attracted to Coffee Grounds
Worms are drawn to coffee grounds for several reasons
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Nutrition Coffee grounds contain proteins, oils, sugars and other nutrients that worms can digest, even after the beans are roasted and brewed The grounds still retain nutritional value
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Grit: The gritty texture of coffee grounds helps worm gizzards grind up food particles since worms lack teeth. This aids their digestion.
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Moisture retention: Coffee grounds hold moisture well, helping keep worm bins from drying out. Worms need moisture to breathe through their skin.
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Natural pesticide: Coffee contains chemicals like caffeine that can deter pests like slugs, snails and insects from invading the bin.
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Microbes: Pre-composted grounds contain beneficial microbes that worms feed on. Fresh grounds are sterile after brewing and need time for microbes to recolonize.
Potential Issues Caused by Too Much Coffee
While worms enjoy coffee grounds, using too much can cause problems in the worm bin:
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Acidity: Coffee grounds are acidic with a pH around 6. High amounts can be harmful to worms.
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Drying out: Dry coffee grounds form clumps that cut off airflow.
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Overheating: The nitrogen in coffee grounds causes excessive heating as they break down. This raises temperatures too high for worms.
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Poor drainage: The fine texture of grounds can clump and restrict drainage.
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Mold growth: The acidity and moisture encourages mold growth.
Solutions to Coffee Ground Problems
There are ways to counteract these potential issues:
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Add crushed eggshells or lime to balance pH. Test bin contents to keep pH between 6-7.
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Keep grounds moist when adding to bin. Mix with juicy wastes like fruit. Cover with bedding.
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Limit coffee grounds to 25-50% of total food waste. Mix in carbon-rich bedding like shredded paper.
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Fluff up and stir bin regularly. Add a drainage layer of rocks or sticks.
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Allow grounds to pre-compost before adding to decrease acidity. Don’t let clump.
Best Practices for Using Coffee Grounds in Worm Bins
Follow these tips to successfully add coffee grounds to your worm bin:
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Pre-compost the grounds for 1-2 weeks before adding to decrease acidity and increase microbes.
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Mix grounds with carbon-rich bedding like shredded paper or cardboard.
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Use pocket feeding to give worms the option to eat the grounds. Don’t mix into the whole bin.
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Limit coffee grounds to 25-50% of total food waste added.
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Keep grounds moist but ensure excess liquid can drain away.
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Bury grounds under bedding to prevent pests and smell.
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Fluff and stir bin regularly to aerate and prevent clumping.
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Monitor temperature and pH. Adjust as needed to stay in optimal range.
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Add grit like eggshells if coffee grounds are the primary food source.
Frequently Asked Questions
Can I put coffee grounds in my worm bin?
Yes, coffee grounds are suitable for worm bins in moderation. They provide nutrition and grit. But too much can cause acidity and heating problems. Follow the best practices to use coffee grounds successfully.
Do worms like used or unused coffee grounds?
Used coffee grounds are better since they have a lower acidity level than fresh grounds. But small amounts of fresh grounds can also be added sparingly.
How much coffee grounds should I add to my worm bin?
Coffee grounds should not exceed 25-50% of the total food waste or bedding material. Start with small amounts and increase slowly while monitoring pH and temperature.
Are coffee grounds acidic?
Yes, coffee grounds are mildly acidic with a pH around 6. Too much acidity can harm worms. Monitor pH levels and add neutralizers like crushed eggshells if needed.
How can I make coffee grounds worm-friendly?
Pre-compost the grounds for 1-2 weeks before adding to decrease acidity and increase beneficial microbes. This makes the grounds more appetizing to worms.
Can I compost coffee filters?
Yes, paper coffee filters are biodegradable and safe to add to your worm bin as well. The worms will slowly break down the filters.
Conclusion
With some careful management, coffee grounds can be a nutritional supplement for your worm bin. Use them in moderation, balance acidity, and keep an eye on moisture, drainage and temperature. Adding coffee grounds with carbon-rich bedding in small doses can provide a helpful boost while avoiding potential problems. Follow the best practices, and you can reuse this common kitchen waste to feed your worms successfully.
Do Worms like Used or Unused Coffee Grounds?
Both used and unused coffee grounds can be used as a food source in vermicomposting. However, used coffee grounds have a lower acidity level than fresh ones, making them a better option for vermicomposting.
Fresh coffee grounds can also be used, but they should be added sparingly and combined with other high-nitrogen materials to counteract their acidity.
Are Coffee Grounds Acidic? Can Coffee Grounds Acidify Your soil?
When using spent coffee grounds as fertilizer, you need to consider the quantity that you will put into the composter, as too much of these can come out too acidic for your worm bin and may eventually harm or burn your worms later on (worms have susceptible skins, thus, their need to be in moist surroundings at all times).
So, coffee grounds should be added in moderation, as the acid in coffee beans can lower the pH level of the compost, making it inhospitable to some types of worms and harming them.
However, if things ever get out of hand and the worm bedding itself gets too acidic, you can always put in some crushed egg shells to help neutralize the system or change the bedding and restart, so you don’t lose your little helpers.You can always save the bedding that you take out for future bedding material for your worms when you harvest the castings/compost.