Do you drink coffee?  My lovely wife and I down two mugs each morning.  We grind our own Peet’s Coffee beans and drip brew the delicious elixir.  A mug of steaming coffee wards off demons from the night before.  Before we realize, we are socially and professionally productive again.
Research has shown that coffee has more benefits for humans than just the caffeine kick.  You’ve probably read about those.  What you may not know is that used coffee grounds are a fabulous source of nutrients for your garden.  We deposit our morning’s spent grounds in our compost bin. None get thrown into the trash (smelly!) or down the drain (clogs!).
Used coffee grounds are rich in nitrogen and other beneficial minerals for the garden.  Nitrogen is your basic green garden rocket fuel.  Dumping grounds into your composting bin will increase the nitrogen percentage of your compost mixture from around 2% (grass and leaves) to 5%. The acidity (or pH) will be nearly neutral 6.5 (acidity in coffee beans is water-soluble and ends up in your mug, not your garden).
Used coffee grounds improves your soil’s structure, making it more “loamy” or easy to dig in, increases healthy water drainage and aeration, and attracts beneficial earthworms and microscopic bugs that make the nutrients available for plants to absorb.
Do you have pests? We certainly do. If you don’t have a compost bin, coffee grounds can be directly spread around flower or vegetable beds to ward off unwanted visitors. The grounds form a barrier that stops snails, slugs, and ants (that carry aphids onto your plants), and earwigs. The spicy aroma also repels rabbits, skunks, raccoons, and unwelcome cats.
If your acid-loving plants are languishing, grind some fresh coffee beans, or buy the cheaper stuff that comes in cans. Spread these unused grounds around the base of your acid-loving plants like azaleas, rhododendrons, roses, berries, or carrots, then water the grounds to release the acid. Hydrangeas in particular will love their fresh Java kick and reward you with bright blue flowers, no matter what their original bloom color. Grounds are less expensive than packaged fertilizer at the local nursery.
You say you don’t drink coffee? Tons of used coffee grounds surround you. Ask a local coffee shop or restaurant to set aside a few pounds for you each week. You can also ask your coffee-drinking neighbors to donate their used grounds. Tell them the Naked Gardener sent you!