Recycled Coffee Grounds Can Rejuvenate Your Plants

By Linda Meyers

April 28, 2012

Recycled Coffee Grounds Can Rejuvenate Your Plants

Once a week we will be featuring a fun and/or educational activity you can try at home or in the classroom. This week the writers on the Heifer Blog have been taking a look at coffee-growing communities all over the world, where hunger and poverty is a common problem. Heifer is helping these farmers by diversifying their income and teaching them about our model for sustainable community development.

You can improve your own sustainability and lessen the negative impact of throwing away garbage that can be recycled. Try this experiment to see the benefits for yourself, with coffee grounds and growing plants.

Do you (or anyone in your house) drink coffee? Many people who do, throw the coffee grounds in the trash when they are done. However, there are many ways you can recycle the grounds, like as fertilizer to help your plants grow healthier and faster. Besides the obvious benefits of recycling instead of throwing away, you can use the natural fertilizer and cut down on the costs of buying fertilizer from the store and/or using chemical fertilizers.

Plant in a small pot
Coffee grounds make a great natural fertilizer

What you need:

  • Two pots (the smaller the better)
  • Potting soil
  • Small stones
  • Seeds
  • Measuring tape
  • Coffee grounds

Coffee grounds make a great natural fertilizer because they are rich in nitrogen, which provides energy to help the bacteria turn organic matter into compost. For the best results, mix the coffee grounds into the soil and sprinkle some around the plants, before you water them.

Put the pebbles at the bottom of both pots. Fill one of the pots with a soil/coffee ground mixture. Fill the other with just soil. Make a trench with your finger in the soil of both pots, and sprinkle seeds in the trench. Cover the seeds with soil, and fully soak the soil with water. Label each pot so you can keep track of your results. The pots should be placed in a well-lit area, and watered every day. Before watering the pot with the coffee ground/soil misture, sprinkle coffee grounds on top of the soil.

Measure the size of the plant with the measuring tape daily, and write the measurements down on a chart with three columns. Column 1 for the date, Column 2 for Pot #1, and Column 3 for Pot #2.

For more information on this experiment and other fun science experiments, go to: For more ideas, read 12 Ways to Recycle Used Coffee Grounds.

You can also check out Heifer's lesson plans and classroom activities related to sustainability, recycling, etc., in the Classroom Resources section of our website.