February 13, 2012

Coffee as Fertilizer, It's Not Just for People Anymore - January 2nd

For 2012 I'm writing this blog to document things our family has done to be more Earth-friendly. This is the January 2nd posting. Hopefully you'll find some helpful ideas and decide to take some action to help promote a healthier planet. I'd appreciate any feedback you have, and if you'd like to share successes you've had I'd like to hear them so we can try to do more.

I haven't always been a coffee drinker, and didn't grow up in a household that drank coffee at all (although my grandparents did). However, in more recent years I've grown fond of the last legal vice and generally have some each day. About a year and a half ago my mother-in-law informed me that not only is coffee delicious, but it is also a great fertilizer.


Coffee is a global commodity, and in recent years it has surged in popularity. According to the United Nations Food and Agriculture Organization (FAO) in 2009, 8,261,487 tons were produced globally. According to PBS Frontline, this amounts to more than 500 billion cups of coffee consumed each year.

Coffee beans have a sizable amount of nitrogen, which is a great fertilizer, and contain around 2% nitrogen by weight. (Here's a Sunset Magazine article that purchased a laboratory analysis of a sample of beans. Also, if you live on the West Coast I highly recommend Sunset for articles on travel, gardening, events, etc. They also regularly publish books on cooking, bird watching, gardening, and many other topics.)

When I first learned of the magical fertilizing properties of coffee I didn't regularly brew or drink coffee, so I didn't have access to used grounds. However, during a winter trip to Kansas I entered a Starbucks and nearly tripped over an overflowing bucket of grounds that was next to the door and available to anyone for free. Little did I know that Starbucks has a 'Grounds for your Garden' program that has been around since 1995 and offers free grounds to customers at their stores.

When I returned from my trip I inquired at my local Starbucks in San Diego about this program and although they weren't participating in the program at the time, I contacted local area manager Joshua Longacre and he got the program going in all of the downtown San Diego stores. I've also since inquired at many other coffee shops and have yet to be turned down on a request for fresh, free grounds.

In addition to helping your plants grow, using grounds in your yard reduces the amount of waste being taken to the landfill.  With the huge amount of coffee produced, that's a big deal.  Two birds with one bean, if you will. The smell of coffee grounds also repels some types of pests, so in addition to promoting growth in your garden they can help deter intruders from eating your carrots.

 Although good for plants, I wouldn't recommend using grounds on houseplants since there's not as much room for the nutrients to disperse and they can make the soil overly acidic.

Suggested action steps:

1) Enjoy coffee (If you don't drink coffee you can get free grounds at most any coffee shop - just ask at the counter and they'll usually be glad to help.)
2) Sprinkle grounds onto garden, lawn, shrubs, trees, etc. I usually pour some water over the grounds too, but you don't have to.  I wouldn't sprinkle one area with grounds more than once a month, and make sure to spread the love. :)
3) Watch plants grow
4) Smile while enjoying shade, fruits and vegetables, or feeling of grass between your toes

Please let me know if you have any comments, compliments, criticisms, or questions regarding this post or have suggestions for future posts. If you'd like to receive future posts via email, enter your email address in the box at the top right labelled "Follow by Email".

Now for a great song with some coffee references:

Thank you!

Category: Food, Garden


  1. Nitrogen and Phosphorus are the most limiting element in the growth of plants. It helps a lot in their growth and development, so says my Ecology teacher

  2. And I understand slugs HATE coffee grounds. Very helpful around hostas and other plants slugs infest.

    1. I haven't been able to tell which pests are turned off by the coffee grounds, but it has definitely helped in my yard with decreasing pests pretty much across the board. The effect on the growth of plants and quality of the soil has been awesome - worms love to eat the grounds so they do their work even more effectively, too.