Why coffee grounds are an excellent fertilizer for cannabis
Coffee grounds are often considered a waste product, but for cannabis growers they are a valuable, natural fertilizer. It contains important nutrients such as nitrogen, phosphorus and potassium – essential elements for healthy plant growth. It also improves soil structure and promotes beneficial microorganisms.
The most important nutrients in coffee grounds
- Nitrogen (N): Promotes vigorous leaf growth.
- Phosphorus (P): Supports root formation and flower development.
- Potassium (K): Strengthens resistance to diseases.
How to use coffee grounds correctly as a cannabis fertilizer
1. fresh or composted?
Fresh coffee grounds can be slightly acidic and lower the pH of the soil. This is often ideal for cannabis, which prefers a neutral to slightly acidic pH (6.0-7.0). If your soil is already too acidic, you should compost the coffee grounds or mix them with other organic materials.
2. direct application vs. coffee grounds tea
- Direct incorporation: Sprinkle a thin layer of coffee grounds on the soil and work it in lightly.
- Coffee grounds tea: Pour water over the coffee grounds, leave to infuse for 24 hours and water the plants with the solution.
3. dosage: Do not overdo it!
Too much coffee grounds can lead to nutrient blockages. A thin layer (approx. 1 cm) every 2-3 weeks is sufficient.
Possible disadvantages and alternatives
Risks of incorrect use
- Mold formation: Damp coffee grounds can become moldy. Dry them before use.
- Over-acidification: Coffee grounds can lower the pH value too much if the soil is already acidic.
Alternative organic fertilizers
- Worm humus – rich in microorganisms.
- Banana peels – Provide potassium.
- Algae meal – Contains trace elements.
Conclusion: Sustainable fertilization with coffee grounds
Coffee grounds are a cost-effective, environmentally friendly way to provide your cannabis plants with nutrients. If you follow the correct dosage and application, you can achieve healthier plants and better yields.