Nutrients

NPK ratios for different growth stages

NPK ratios for growth phases: seedlings 1-1-1, vegetative 3-1-2, early flowering 1-3-2, late flowering 1-3-3 — plus calcium and magnesium throughout.

Optimum NPK ratios change: seedlings 1-1-1, vegetative 3-1-2, early flowering 1-3-2, late flowering 1-3-3. Calcium and magnesium are constantly important (Ca:Mg = 3:1). Adjust EC values accordingly: seedlings 0.4-0.8, vegetative 1.2-1.6, flowering 1.6-2.2. Avoid over-fertilisation - less is often more.

Frequently Asked Questions

What are the ideal NPK ratios for the vegetative phase of cannabis?

During the vegetative phase, the NPK ratio should be approximately 3-1-2 or 4-2-3 to promote the growth of leaves and stems.

How do I adjust the NPK ratio during the flowering phase?

During the flowering phase, the NPK ratio should be adjusted to approximately 1-3-2 or 2-4-4 to support flower formation and promote fruit growth.

How often should I apply fertilizers with specific NPK ratios?

Fertilizer should generally be applied every 1–2 weeks, depending on the growth stage and the specific needs of the plants.

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