Question
How often should I use coffee grounds on my Acid-loving plants?

Answer
Dear Julee:

Studies have shown the effective role that spent coffee grounds can have in a garden as a fertilizer.  Due to its high nitrogen content, spent coffee grounds contain properties that is excellent in plant health.  As nitrogen is a crucial component of DNA, RNA, and proteins that plants need to build themselves, coffee is becoming increasingly used as a fertilizer.  Additionally, recent studies have shown that spent coffee grounds also contain potassium, phosphorous, and other trace elements that only assist the development process for a plant.  It is particularly effective for roses, as many gardeners swear that roses love coffee grounds as a fertilizer.

Because of the higher nitrogen content, I suggest that you apply coffee grounds on your acid loving plants every 3 weeks during the spring and summer months.  During fall and winter months suggest applying every 6 to 8 weeks.

Sincerely,

Mack Jean
AllExperts
Master Gardener
Tennessee