A Little Compost with that Latte?

Did you know that Starbucks has a corporate policy of making its used coffee grounds available free as a soil amendment or composting ingredient?

For months I've been working up to introducing myself to our neighborhood Starbucks and starting regular pickups of grounds for my compost pile. A fellow gardener here in the District of Columbia is a prolific composter and coffee grounds have become one of his primary ingredients. He attached a trailer to his bicycle and pedals around town, stopping at various Starbucks stores and harvesting their used grounds.

I don't plan on using coffee grounds quite to that extent. But coffee grounds do contain a fair amount of nitrogen and therefore are considered--along with grass clippings and other kitchen scraps--a "green" material to be mixed with "browns" such as leaves and newspaper in the compost pile. Nitrogen feeds the bacteria that heat up the pile and ignite the decomposition process.

So this week I finally introduced myself to the local Starbucks. The manager on duty looked surprised when I told her what I wanted. She'd never heard of the Starbucks coffee grounds policy, and apparently no one had ever asked for the used grounds at that particular store before. Nevertheless, she took my contact information and promised to have a bag of grounds ready for me to pick up later in the week.

Imagine my chagrin when I entered the store at the appointed hour and found a different manager on duty. No grounds had been saved for me. I was very disappointed. But then this particular manager--Vanessa is her name--explained that she had seen my note and knew all about composting with coffee grounds. She had moved from a Starbucks location in California where they are quite used to giving away their used grounds to gardeners. "We even have tags that we put on the bags explaining how to compost with the coffee grounds," she explained.

Even though the grounds had not been saved for me as promised, Vanessa would not let me walk away empty-handed. "We have some bags of expired beans," she said cheerily. "Would you like me to grind them up for you?"

You bet I would. So I waited while Vanessa ran 15 pounds of coffee beans through the grinder and bagged them for me. Here you see them waiting to be mixed into the compost pile I started last fall.

Coffee grounds are slightly acidic but entirely organic matter, making them a suitable soil amendment all on their own. Once the micro-organisms start feeding on them, the nitrogen contained in the grounds is slowly released to feed your garden plants. Coffee grounds also contain potassium, calcium and magnesium. Both Starbucks and Sunset magazine have run tests on coffee grounds to identify specific nutrients.

Unless it's decaf, I don't drink coffee anymore. But I can easily see these free coffee grounds becoming addictive. Thanks, Vanessa. And thanks, Starbucks, for thinking of us composters.