Coffee in the garden

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(HOST) The garden has long been a pleasant setting for a tea or coffee break, but commentator Charlie Nardozzi says that the garden itself derives substantial benefit from an occasional cup.

(NARDOZZI) I’m not a coffee drinker, but my garden is. The world production of coffee is more than seven million tons a year. Every day across America, millions of pots of coffee are brewed and millions of pounds of wet grounds, filters and bags are thrown in the trash.

That’s a shame. Coffee grounds turn out to be an excellent garden fertilizer. Not only are these grounds loaded with organic matter that earthworms love, there are nutrients for your plants in those grounds as well. Coffee grounds contain two percent nitrogen fertilizer and smaller amounts of phosphorous, potassium and trace minerals.

The benefits of coffee grounds to gardens have not gone unnoticed. Starbucks is now offering bags of used grounds at many of their cafes. The colorful Grounds for Gardens bags are free to patrons. They’re filled with fine espresso coffee grounds and do not include filters, so they’re easy to work with. If your local Starbucks doesn’t have grounds for you, the ones from your own kitchen, workplace, neighborhood diner or even gas station would be fine. Just store the grounds in a plastic bag until you’re ready to use them. If the carbon filters are included, the grounds can be safely composted and the end product used in the garden.

Here’s how to use your coffee grounds in your yard: Spread a one- to two-inch-deep mulch layer under acid-loving shrubs, such as rhododendrons, evergreens and blueberries. Even roses seem to appreciate the coffee buzz. Don’t apply a thicker mulch layer because it might prevent water from penetrating into the soil, and the grounds may get moldy. You can also mix the grounds in with your potting soil to give it a boost. Add coffee grounds so they comprise no more than 25 percent of the total soil volume. You can create a diluted coffee tea by soaking the used grounds in water and applying the water as a fertilizer to plants. Soak about one half pound of grounds in a five- gallon bucket of water overnight and then apply the solution to your plants.

There even has been some research that suggests coffee and coffee grounds repel slugs. Researchers in Hawaii applied coffee grounds and sprayed coffee on plants. In some cases, the slugs stayed away. It seems it’s the caffeine in the coffee that repels the slugs. Research- ers applied a one to two percent caffeine solution to ward off these pests (most coffees have a .1 percent solution of caffeine). So if you try this home remedy in your yard, you’ll have to use the most potent coffee blend you have.

No matter what flavor coffee you’re drinking, save the grounds for your garden. Oh, and don’t worry. Unlike humans, your plants won’t get addicted to the caffeine, start requesting exotically flavored coffee blends or get cranky in the morning if they haven’t had their first cup of coffee for the day.

This is Charlie Nardozzi in Shelburne.

Charlie Nardozzi is an all-around gardening expert with a special fondness for tomatoes and roses.

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