Potassium (K) is one of three macronutrients for growing cannabis along with nitrogen (N) and phosphorus (P), typically represented on commercial fertilizers with their ratio identified as N-P-K. Potassium is a mineral that is found naturally in soil with clay soils being particularly rich in this mineral.
Potassium supports critical biological processes and functions for healthy cannabis plants such as:
- Increases disease resistance
- Increases resistance to frost
- Important for photosynthesis
- Strengthens plant tissue and sturdiness
- Stimulates early growth
- Increases bud density and size
- Improves efficient water use
Potassium is important during all cannabis growth stages and particularly during the flowering stage to promote bud development. Without enough potassium, plants will show signs of deficiency and yields will suffer. An early sign of a potassium deficiency is yellowing leaves that may begin to curl, this may begin on older leaves towards the bottom of the plant. Test your soil and adjust nutrients accordingly.