Coffee grounds are an excellent organic fertilizer that enriches the soil with essential nutrients, improves drainage, and boosts plant health. They contain nitrogen (N), potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), and antioxidants, making them a great slow-release fertilizer for many plants.
Benefits of Using Coffee Grounds as Fertilizer
✔ Rich in Nitrogen (2% by weight) – Promotes leafy growth in plants.
✔ Improves Soil Structure – Enhances aeration, drainage, and moisture retention.
✔ Boosts Microbial Activity – Encourages beneficial earthworms & soil bacteria.
✔ Natural Pest Repellent – Deters slugs, snails, and ants due to its caffeine content.
✔ pH Balance – Slightly acidic, suitable for acid-loving plants.
How to Use Coffee Grounds as Fertilizer
1️⃣ Direct Soil Application (Mulching & Composting)
Instructions:
- Spread a thin layer (½ inch) of used coffee grounds around the base of plants.
- Mix into the topsoil to prevent mold growth.
- Combine with dry organic matter (leaves, straw, sawdust) for balance.
2️⃣ Coffee Ground Tea (Liquid Fertilizer)
Instructions:
- Add 2 cups of used coffee grounds to a 5-liter container of water.
- Let it steep for 24 hours to extract nutrients.
- Strain and use as a liquid fertilizer spray or pour at the base of plants.
3️⃣ Compost Booster
Instructions:
- Mix coffee grounds into your compost bin (20% of total material).
- Helps speed up decomposition and adds nitrogen for a balanced compost mix.
Best Plants for Coffee Grounds Fertilizer
✅ Acid-Loving Plants: Blueberries, Azaleas, Rhododendrons, Camellias
✅ Leafy Greens: Spinach, Kale, Lettuce, Cabbage
✅ Flowering Plants: Roses, Hydrangeas, Daffodils, Orchids
✅ Fruiting Plants: Tomatoes, Strawberries, Carrots, Radishes
Important Tips & Precautions
Use Moderately – Too much coffee can compact the soil and hinder water absorption.
Avoid Fresh Grounds on Soil – Fresh (unbrewed) coffee grounds are too acidic and can stunt plant growth.
Mix with Other Organic Matter – Combine with compost or dry materials for better soil balance.