Nutrient Management of Cannabis
Cannabis originates in Southeast Asia and includes three species: C. indica, C. sativa and C. reduralis. It is a dioecious, annual plant.
CANNABIS GROWING CONDITIONS
SOIL and pH LEVEL
Cannabis can be grown in soil or soilless media. The optimal pH for healthy growth ranges between 5.9 and 6.5. The pH level should be controlled during cultivation.
CLIMATE
The optimal temperature during the day is 75°F to 86°F (24°C to 30°C). Higher or lower temperatures will reduce flowering rates and will have a negative effect on yield and quality.
LIGHT CONTROL
When growing hydroponically indoors, the duration of the growth stages can be controlled by changing the exposure of the crop to varying light intensities. When daylight time is between 16-24 hours per day, cannabis plants will undergo rapid vegetative growth. When daylight hours begin to shorten, the plants will go more quickly to an indication of flowering.
When using artificial light, the light intensity will have an effect on the total growth, growth duration, water management, and nutritional demand of the cannabis plants.
NUTRIENT REQUIREMENTS – LOW LIGHT TREATMENT
| N (ppm) | P (ppm) | K (ppm) | Zn (ppm) | Mg (ppm) | B (ppm) | |
| Stage Name | ||||||
| First 2 weeks | 80 | 40 | 140 | 0.3 | 50 | 0.3 |
| Growth | 300 | 60 | 215 | 0.3 | 60 | 0.3 |
| Flowering | 100 | 70 | 200 | 0.3 | 60 | 0.3 |
NUTRIENT REQUIREMENTS – INTENSE LIGHT TREATMENT
| N (ppm) | P (ppm) | K (ppm) | Zn (ppm) | Mg (ppm) | B (ppm) | |
| Stage Name | ||||||
| First 2 weeks | 100 | 40 | 140 | 0.3 | 50 | 0.3 |
| Growth | 350 | 60 | 215 | 0.3 | 60 | 0.3 |
| Flowering | 110 | 70 | 200 | 0.3 | 60 | 0.3 |
*The full list of nutrients is available in SMART Fertilizer Software in the software.
GROWTH CYCLES OF CANNABIS
ESTABLISHMENT
The final cannabis product is usually female-only without female pollination. To prevent male differentiation or crop variation, cannabis is usually planted as rooted cuttings. After a short time for establishment (about 14 days from planting), the vegetative phase will start.
GROWTH (VEGETATIVE) PHASE
The vegetative phase lasts about 45 days, during which time the plant requires a significant amount of light strength. Nutrient requirements are high, especially nitrogen, potassium and micronutrients.
FLOWERING PHASE
The duration of the flowering stage varies among different species and can range from 50 to 140 days. This growth stage will start when the darkness photoperiod exceeds 10 hours. During the flowering stage, the nutrient requirements of cannabis change as well; the plant will require larger amounts of potassium and less nitrogen (which encourages vegetative growth).
NUTRIENT MANAGEMENT
When growing hydroponically, optimal conditions can be maintained, so as to achieve maximum yield potential at the best quality.
In hydroponic systems, fertilizers are provided to cannabis by applying a nutrient solution, prepared according to its current nutrient requirements, growing conditions and nutrient content of the source water. We recommend testing the source water periodically, in order to obtain the exact fertilizer formula that will meet the crop demand.
The main objective of crop nutrient management is to apply the right rates of nutrients at the right time, based on the dynamic conditions. The best results can be achieved by adjusting the applied nutrient solution, based on the variations in the growing conditions, such as temperature, humidity, source water quality, pH, salinity (EC/TDS), and the composition of the nutrient solution (especially if recycled). These parameters are easy to monitor, and should be measured frequently.
Measuring the dynamic parameters is essential and easy to do. The main challenge in nutrient management is translating the information into actionable actions that will improve the yields and quality. In SMART FERTILIZER software, we created a specific section for hydroponic and fertigation where for each growth stage we suggest different amounts of nutrients but also different pH and EC (Electrical Conductivity). In this section, there is also a feature called ‘Drainage Tool’ which helps in understanding and re-adjusting the fertigation automatically according to the analysis of the ‘drained solution’ from your substrate/pot.
For this, growers need a specific recommendation system (a decision support tool that will help them make the right decisions) based on all the factors that affect cannabis growth.
- Recommends the ideal fertilizer mixture/ blends
- Saves up to 50% on fertilizer costs
- Comprehensive data on hundreds of crop varieties
- Interprets test results for any extraction method
