Old coffee grinds really do enhance the flavor of many crops , cantaloupe, tomatoes, melons. No study to prove it , by it is said you get bigger melons if you use coffee grinds.
As they break down, the grinds will release nitrogen into the soil. Other nutrients in Coffee Grinds are phosphorus, potassium, magnesium, and copper.
"Coffee grounds, as an organic material, can be added to your compost pile. Worms like coffee grounds, so you may want to put a layer of coffee on the bottom of your pile to attract worms. " - Cornell UniversityThey also serve well in Worm Composting
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