Instead of dumping used coffee grounds in the trash or washing into the garbage disposal, you can add them to your compost pile. They've been pulverized into tiny bits, so they will decompose rapidly.
You can also sprinkle coffee grounds around such acid-loving plants blueberries, cranberries, apples, pears, citrus, strawberries and bananas. A
quarter-inch application every month or so will help to keep the soil a
little on the acidic side.