Understanding NPK ratios for cannabis: high nitrogen (20-10-10) in vegetation, more phosphorus (10-30-20) in flowering — core nutrient principles explained.
NPK stands for nitrogen (N), phosphorus (P) and potassium (K) - the main nutrients for cannabis. Vegetation phase: High nitrogen content (e.g. 20-10-10) for leaf growth. Flowering phase: Less nitrogen, more phosphorus (e.g. 10-30-20) for flower formation. Potassium is important for cell structure in both phases. Over-fertilisation is shown by burnt leaf tips. Under-fertilisation is shown by yellow leaves. Measure EC values for precise dosing. Organic vs. mineral fertilisers have different NPK profiles.
The NPK ratio indicates the content of nitrogen (N), phosphorus (P), and potassium (K) in a fertilizer, with the numbers representing the proportions of these nutrients relative to one another.
Fertilizers with a high nitrogen content (e.g., 20-10-10) should be used during the vegetative phase to promote plant growth and leaf development.
Phosphorus (e.g., 10-30-20) is crucial during the flowering stage, as it promotes flower formation and fruit development, resulting in a higher-quality harvest.
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