Perk Up Your Plants with Coffee Grounds
Gardener’s Notebook
By Joshua Burman Thayer | Illustration by Charmaine Koehler-lodge
As of January 1, 2022, Senate Bill 1383 requires that all California residents separate organic waste from other garbage. You may already have been doing the right thing by putting food scraps in your green barrel, but when you separate your used coffee grounds into their own bucket, you have captured a natural and beneficial soil amendment for your garden.
First, identify heavy feeders in your garden: Many California native plants and Mediterranean plants (e.g., sages and lavenders) do not want such rich nutrients as coffee grounds regularly added around their roots, so stick to feeding your perennials and vegetables. Tomato, squash, pumpkin, corn, apple, pear, plum, cherry, avocado, roses, camellias, magnolias, and azaleas all welcome regular nutrients.
Do the sugar shake: If you left your used grounds out all day, you may be able to just take them outside and gently sprinkle them all around any plants you want to feed. Each time you spread coffee grounds, find new destinations for them, and avoid clumping a whole handful of grounds in any one area, as they are very acidic.
If you are working on a large gardening project: See if your local coffee shop will let you pick up bags of spent grounds. Shops are usually very willing. Repeat this amendment once per month is you are getting the grounds all at once.
Don’t have an actual garden? You can help feed and enhance the soil biology anywhere by “sugar shaking” coffee grounds on any untended piece of ground.
Note: If you use paper coffee filters, they could go in your backyard compost heap, or you may prefer to toss those into your green barrel.
Find Josh’s short YouTube video on using coffee grounds in the garden here: “How to use Coffee with Plants – Josh (the plant guy).”
Joshua Burman Thayer is a permaculture designer and educator. A regular contributor to Edible East Bay and Mother Earth News, he also offers valuable gardening advice monthly in our e-newsletter, East Bay Appetizer, which you can subscribe to at our website. Learn more about Joshua’s work at nativesungardens.com, and follow him on Twitter @nativesungarden.