Yeah, coffee grinds. We use an iCoffee machine here and do not use the k-cups that you buy in the store but rather the ones that are refillable. Part of the reason is because those things are littering landfills all across the world and part of the reason is because I'm cheap and it is less expensive to use the refillable ones. I actually have a clear vinyl 5/8" hose in the back yard that I use to clean them so we do not get a garden hose smell on them when I wash them out on a daily basis. Some of the grinds go in our composter and some I save for the bushes in the front. Most people just throw out their grinds but they are doing a disservice to their flowering bushes if they have any. Here is the result of coffee grinds for fertilizer for one of our azaleas. Hop on the coffee grinds train folks... you are getting free fertilizer and will have bushes that look like they are on the 13th hole at Augusta.