Testing Plant Soil Nutrients

Cannabis Plant NPK Nutrient Needs Change

Industry can offer guidelines on the primary nutrient additions at various growth stages, for example;

  • Vegetative: Nitrogen (N) 300 ppm, Phosphorous (P) 60 ppm and Potassium (K) 215 ppm

  • Flowering: Nitrogen (N) 70 ppm, Phosphorous (P) 100 ppm and Potassium (K) 200 ppm

How much do you need to add?

  • Too much or too little can have consequences

  • Every strain will have different needs and water, temperature and other conditions will effect nutrient consumption

Cannabis Plant Soil NPK Nutrients Needs throughout plant lifecycle
Animation of how UV-VIS Spectrophotometryworks

How do you accurately measure nutrient content?

UV-VIS Spectrophotometry technology is based on the physics concept that molecules will absorb energy of different wavelengths of light. Therefore, measuring the wavelength at maximum absorption energy can identify what the molecular group is. 

The higher the concentration of molecules the greater the energy absorption.  By using a standard of known concentration as a reference, the unknown sample concentration can be determined.

What does it measure?

  • Exact N, P or K concentration levels or other elements in a sample solution.

  • Compare an initial sample, to samples taken though the growth cycles to determine the rate of nutrient consumed.