Coffee grounds in the garden - When and where? 
You may have noticed your local coffee shop offering free coffee grounds to gardeners. Although it's true that coffee grounds can act as a slow-releasing fertilizer for some plants, it can invite mold and other problems if not properly used. So, here's the break down of when and where to use coffee grounds in your garden.
Coffee grounds add acidic nutrients into the soil, so they are most beneficial for plants that yearn acidic earth, like roses and columbine. The great people at
Crescent Bloom organized a list of acidic soil loving plants. Evergreens also pine for these roasted dregs in their root system.
Grounds are are also full of other nutrients like iron, and the caffeine can encourage plant roots to spread. However, grounds should only be applied fresh and in a thin layer once a year. If you apply them too thick, they are more likely to mold and that causes more problems.
Coffee and gardening
Every day across America, Asia and Europe, millions of pots of coffee and tea are brewed, and the millions of pounds of wet grounds, filters and bags thrown in the trash. This is both wasteful and foolish.
Coffee by-products can be used in the garden and farm as follows:
- Sprinkle used grounds around plants before rain or watering, for a slow-release nitrogen.
- Add to compost piles to increase nitrogen balance. Coffee filters and tea bags break down rapidly during composting.
- Dilute 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; let sit outdoors to achieve ambient temperature.
- Mix into soil for houseplants or new vegetable beds.
- Encircle the base of the plant with a coffee and eggshell barrier to repel pests.
- If you are into vermi-posting, feed a little bit to your worms