Thursday, April 15, 2010

Coffee Grounds Good For The Garden?

I'm sure we have all seen the free "Grounds for your Garden" in our local Starbucks. Coffee grounds sound like a good soil amendment, I know they always make me feel better, if only for a short while. But are coffee grinds actually good for your vegetable garden? I found a very informative article on Gardens Alive that had several good points:

Raw grounds straight into the soil.

First it's "not recommended [to add] raw ingredients [to your garden] before composting". Seeing as "coffee grounds alone are highly acidic [they would be] best for plants like blueberries that thrive in very acidic soil". Because grounds are so high in acid and nitrogen you "risk creating a 'mold bloom' where you spread them".

Okay, then I will compost the grounds and add them to my blueberries.

The author recommends "adding a cup of agricultural lime [or hardwood ashes] to every ten pounds of grounds before you add them to your compost pile".

Well grounds do have lots of good nutrients right?

Typical grounds contain "1.5% Nitrogen...also alot of Magnesium and Potassium, both of which plants really like, but not a lot of Phosphorus (the fruiting or flowering nutrient) or calcium, a mineral that many plants crave, and whose lack helps explain the recalcitrant acidity".

Here in California they mention it might do more good than bad due to our high alkaline content. I think most organic soil amendments in moderation, mixed with a compost pile that has good levels of green and brown, will do more good then harm.


  1. My husband and I bring all of our compostable stuffs home from work, which always includes LOTS of coffee grounds. They always go directly into the compost bin.

  2. Hi JT, I'm more of a tea kinda girl and I throw my tea bags onto the compost heap too. It all helps! UDG