My grandmother always told me there was nothing better than coffee grounds for azaleas, and she should know – her yard was a showplace! Every year, people would pull up in front of her home near 16th and Colorado Ave., N.W. in Washington to take photos of her amazing azaleas.
I’m not as religious about it as she was – mostly because we don’t drink much coffee at home – but I do spread coffee grounds around my azaleas whenever we have them. In fact, sometimes I wonder if it would be beneficial to just buy a bag of coffee and use it straight out of the bag. Instinct tells me that would be too acidic even for acid-loving plants like azaleas, rhododendron, dogwood, holly, hydrangea, juniper, magnolia, pine, and blueberries.
Today I came across a recent article on this very topic: Anna Hackman’s Coffee Grounds, Garden Friend or Foe? The author reports on her experience using coffee grounds to rescue some sickly rose bushes. Intrigued by the good results, yet questioning if it really was the coffee grounds (or was it coincidence?), she embarked on a quest for real research regarding this practice.
She found a study on the Gardens Alive website, titled Using Coffee Grounds Correctly, which includes a conversation with Will Brinton, founder and Director of the Wood’s End Research Laboratory in Maine, testers of soils, composts, and raw ingredients used in composting. I won’t try to re-cap the interview here because I think you’ll find it interesting to read the entire post.
She also spoke with a researcher and training manager at Rodale Institute, Dr. Paul Hepperly, who indicated coffee grounds are solely a soil amendment and not a fertilizer. It was his recommendation to side-dress plants with no more than one inch at a time, and to add more coffee grounds only after the original ones decompose.
I guess the bottom line is this: A little coffee can be a gardener’s friend in more ways than one – at the breakfast table AND in the garden. ‘Think I’ll head on down to Starbucks and see if they have some coffee grounds they’d like to give away!
Source: Margaret Woda, Focus On Crofton