Coffee grounds are an excellent addition to compost piles, acting as a "green" material that provides nitrogen. They should be mixed with "brown" materials (like dried leaves or cardboard) to create a balanced compost.
Benefits for Specific Plants
Used coffee grounds are particularly beneficial for acid-loving plants, such as:
Blueberries, Azaleas, Rhododendrons, Tomatoes, Cucumbers, Beans, Broccoli, Strawberries
However, avoid using them excessively, as they can increase soil acidity and potentially harm plants that prefer neutral or alkaline soils.
Additional Uses
Beyond fertilization, used coffee grounds can also:
Repel pests: Sprinkle them around areas where insects gather
Improve soil texture: When mixed into the soil, they can enhance aeration and drainage
Grow mushrooms: Coffee grounds can serve as an excellent substrate for mushroom cultivation due to their nutrient content
Cautions
While coffee grounds can be beneficial, it's advisable not to apply them directly in large quantities to avoid compacting the soil and hindering moisture absorption. Instead, use them sparingly and consider composting first for optimal results