Rhododendrons Drink of Choice: Coffee

I read lots of nursery and gardening publications and I’m always keeping an eye out for items that might be of interest to Random Acts of Gardening readers. I came across “Tips for Beginners” in the 2011 winter edition of the Journal American Rhododendron Society and wanted to pass it along.

I know some designers and garden writers scoff at Rhododendrons: Been there, done that! I wholeheartedly disagree. They provide structure, and in some cases some really great looking leaves, year round. And I look forward to their long-lasting blooms. Admittedly, I am struggling with root weevils in one area of my garden and something that looks gray and fuzzy on the underside of leaves on a few rhodys; but on the whole, they are easy plants to grow. So here’s what Noni Godfrey Courtenay from British Columbia, Canada, has to say about making Rhodys easy for beginners. Apparently, people in Portland and Seattle aren’t the only ones that enjoy their coffee…

Coffee Grounds & Fish Compost for Rhodos

Rhodos use a lot of energy when blooming and then immediately begin producing new growth for the following year’s bloom. So it’s no surprise that many rhodos show signs of yellowing leaves at this time. A malnourished plant is not only unattractive, it’s also susceptible to pests and diseases.

Easy ways to treat—better yet, prevent—this problem is to fertilize rhodos twice yearly: immediately after blooming ends and again in early summer. A controlled-release organic fertilizer is best since these plants are shallow-rooted and a high powered chemical fertilizer can easily burn the roots, perhaps even killing the plant.

Rhodos must have acidic soil in order to access and absorb nutrients, so if your rhodo is in sweet soil, feeding it will be a waste of time and fertilizer. Here is an easy way to mulch, acidify the soil, recycle your coffee grounds and nourish your rhodo, azalea or camellia.

Recipe for Rhododendron Mulch

8 quart bag of fish compost, such as “sea soil”
1 cup organic all-purpose fertilizer
¼ cup Epsom salts
8 cups used coffee grounds

Blend all ingredients and apply a 2” layer to the drip line twice a year, in early spring and early fall.

I wonder what Barney, my adorable golden retriever, will do with the fish compost! The rest of it sounds easy and economical. You can often pick up free bags of coffee grounds from your local Starbucks.