A Little Dirt with Your Coffee?

May 11th, 2012 | Simcha Weinstein | Comments Off on A Little Dirt with Your Coffee?

As we move into gardening season it appears that one of the latest compost trends (and yes, there are trends in composting) is maximizing the use of your coffee grounds. It turns out they make excellent compost for your garden, and can even double as a great natural fertilizer for your yard.

Coffee grounds really are a nice addition to any composting effort. They are a great nitrogen source with a C/N ratio of 20:1. The concern with using coffee grounds in your compost has always been that coffee is considered a pretty acidic beverage and it would greatly disrupt the pH balance of your soil, creating a mix that is too acidic. The good news is that while roasted coffee is fairly acidic, it appears that almost all of the acid is water soluble and is extracted during brewing. Used grounds have essentially neutral pH, although the coffee beverage produced is rather acidic.

There seems to be a fair amount of anecdotal evidence suggesting that worms are attracted to coffee grounds, and of course worms serve as a great soil conditioner.

If you decide that you want to heavily incorporate coffee grounds into your compost mix and need grounds beyond what your own coffee drinking can generate, keep in mind that you typically don’t want the grounds to exceed 25% of your compost mixture. But if you are a serious composter you can easily find grounds outside of your own drinking capacity. Starbucks is actually a very willing partner with this. They have a corporate policy of trying to reduce waste and will, at most locations, provide you with coffee grounds simply by asking.

Your coffee grounds will also make for excellent yard fertilizer. A spread rate of one cubic yard per 1,000 square feet of lawn should work and it’s best to spread it as a very thin layer. Again, anecdotal evidence, especially from folks who use it on their lawns, suggest that earthworms really like coffee grounds. While this is great for the soil, if there is a downside to an abundance of worms, it’s moles. And while moles are a natural part of any healthy ecosystem, they can be disruptive to your yard. So, it’s best to be prepared. Along with greener pastures, come a few new friends.

Once the coffee grounds are spread over your grass, you can brush them in using a push-broom and you can also water the treated area. For about the first week after the grounds are applied it may smell like coffee is brewing in your yard, particularly during the heat of a very sunny day. You can reapply this natural fertilization treatment every month or two, and watch your lawn turn an amazing rich green color. Of course, if you decide to drink more coffee, in an effort to create enough fertilizer for your yard, you may find that you’ll have the energy to apply your coffee grounds with much greater frequency : )