Did you know coffee grounds aren’t just for acid-loving plants? They’re a versatile, eco-friendly addition to any garden. Not only do they benefit plants, but earthworms love them too! Here’s why coffee grounds are a gardener’s secret weapon—and how to use them effectively.

Why Use Coffee Grounds in the Garden?

Adding spent coffee grounds to your garden offers numerous advantages. They’re a natural, organic matter that can improve soil structure, enhance moisture retention, and boost fertility. Plus, repurposing used coffee grounds reduces waste, keeping them out of landfills.

Benefits of Using Coffee Grounds in Your Garden

1. Enrich Soil Structure: Coffee grounds improve soil texture and moisture retention, whether used in-ground or in containers.
2. Nutrient Boost: Coffee grounds provide small amounts of nitrogen, phosphorus, potassium, calcium, magnesium, copper, and sulfur.
3. Composting Power: When mixed with “brown” materials like leaves or straw, coffee grounds speed up composting by generating heat.
4. pH Adjustment: Over time, coffee grounds may lower soil pH slightly, with an average pH of 6.2. This makes them suitable for acid-loving plants.
5. Fungal Protection: Coffee grounds can suppress certain fungal rots and wilts.
6. Earthworm Magnet: Earthworms love coffee grounds, which can lead to healthier, more aerated soil.

How to Use Coffee Grounds for Plants

• Soil Amendment: Sprinkle coffee grounds directly onto soil in gardens, flower beds, and vegetable patches, till in for best results. For guidance, use up to 6 pounds per 100 square feet.
• Mulch: Scatter coffee grounds lightly over mulch or lawn and water afterward.
• Composting: Add coffee grounds to your compost pile (10-20% of total material). They boost the heat, accelerating decomposition.
• Indoor Plants: Sprinkle coffee grounds on top of the soil or mix into potting soil during repotting.
• Natural Insect Repellent: Coffee grounds can help deter slugs, ants, and other garden pests.
• DIY Liquid Fertilizer: Soak ½ to 1 pound of wet coffee grounds in 5 gallons of water for 24 hours, then apply to plants as a natural liquid fertilizer.

Plants That Prefer Coffee Grounds

Certain plants, especially acid-loving varieties, benefit most from coffee grounds. Consider adding coffee grounds to the following:

• Azaleas

• Hollies

• Hydrangeas

• Evergreens

• Blueberries

Rose growers have used coffee grounds for years, side-dressing plants with a half-inch layer and reapplying after decomposition.

Plants to Avoid Using Coffee Grounds With

Not all plants love coffee grounds. Avoid using them around:

• White and red clover
• Alfalfa
• Italian ryegrass
• Chinese mustard
• Asparagus ferns
• Geraniums
• Inch plants

Get Free Coffee Grounds for Your Garden

Even if you don’t drink coffee, you can pick up used grounds from your local coffee shop. Use these nutrient-rich grounds to enrich your soil and keep your garden healthy and thriving.

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