Cannabis Watering and Feeding Schedule by Stage
Use this as a starting framework, then adjust based on how your specific plants respond. Genetics vary more than any chart can capture.
Stage targets
Values are total dissolved solids on the 500 scale, including what is already in your water.
- Germination: plain pH'd water, 6.0-6.5, no nutrients
- Seedling: 150-300 ppm, quarter strength, Cal-Mag if on RO
- Early veg: 400-700 ppm, nitrogen-heavy base
- Late veg: 700-1000 ppm, plus silica for stem strength
- Early flower: 900-1200 ppm, shift toward P and K
- Late flower: 1000-1400 ppm, K-heavy, then taper
- Final week: plain water or heavily reduced feed
Additives worth using
Cal-Mag for RO and coco growers, silica for stem strength and stress tolerance in veg, and mycorrhizae at transplant to speed root colonization. Most other bottles in a store are optional.
Adjust to the plant
Slight tip burn means back off by 100-200 ppm. Pale, slowly-yellowing lower leaves in mid-veg means feed more. The chart is a hypothesis; the plant is the data.
Frequently asked questions
- Should autoflowers use these numbers?
- Run autos at roughly 70-80% of these values. They are smaller and burn easily.
Keep reading
Legal notice: We do not promote or encourage breaking the law. This site is for adults 21+ growing in states and jurisdictions that have legalized cannabis cultivation, and who are following all legal growing guidelines, plant count limits, and permit requirements that apply to them.