Each day in America, millions of pots of coffee and tea are brewed, and millions of pounds of wet grounds, filters and tea bags are thrown in the trash. This is both wasteful and foolish. Fortunately, the Coffee Ground Rescue Project is helping to reduce the amount of grounds being sent to the incinerator in Peekskill while helping to build soil fertility in Westchester County. Promoting the idea that coffee grounds are great in the garden, they offer the following tips:

• Sprinkle used grounds around plants before rain or watering for slow-release nitrogen
• Add them to compost piles to increase nitrogen balance; coffee filters and tea bags break down rapidly during composting
• Dilute grounds with water for a gentle, fast-acting liquid fertilizer; use about a half-pound can of wet grounds in a five-gallon bucket of water and let sit outdoors to achieve ambient temperature
• Mix grounds into soil for houseplants or new vegetable beds
• Encircle the base of each plant with a coffee and eggshell barrier to repel pests
• If you are into vermi-composting, give some grounds to your worms!

Coffee grounds are 1.45% nitrogen and they contain calcium and magnesium, adding some trace minerals that may not be found in other organic material.  Coffee grounds are a green material (same idea as grass clippings), so you should match them with at least equal amounts of brown material (leaves) unless your browns are already too high.  

The staff members at The Black Cow Coffee Company in Pleasantville are very supportive of rescuing grounds. In fact, they’ve been saving them daily since they opened last summer.

Dr. Susan Rubin is a master composter and recycler. To join the Coffee Ground Rescue Project or create one in your community, contact her at [email protected] or 914.844.3776.