Hydroponic cultivation

Growing cannabis hydroponically offers many advantages, such as faster growth and higher yields, but it also requires special attention and care. Here are some important aspects to consider when growing cannabis hydroponically:

1. Selecting the hydroponic system

There are different hydroponic systems you can choose from:

  • Deep Water Culture (DWC) : Plant roots hang in an aerated nutrient solution.
  • Nutrient Film Technique (NFT) : A thin film of nutrient solution flows over the roots.
  • Ebb and Flow (Flood and Drain) : Nutrient solution is periodically pumped into the root zone and then drained.
  • Drip System : Nutrient solution is continuously dripped onto the medium and the roots.
  • Aeroponics : Roots are sprayed in the air and not immersed in a liquid.

2. Water quality

  • pH value : The pH value of the nutrient solution should be between 5.5 and 6.5 to ensure optimal nutrient absorption.
  • EC/TDS value : Electrical conductivity (EC) or total dissolved solids (TDS) measure the concentration of nutrients in the solution. Keep the EC value between 1.0 and 2.5 mS/cm.
  • Water source : Use purified or distilled water to avoid contamination.

3. Nutrients

  • Hydroponic nutrients : Use special hydroponic nutrients as they are formulated to remain stable in aqueous solution and can be easily absorbed by the plants.
  • Nutrient ratio : Pay attention to the correct ratio of macro- (N, P, K) and micronutrients (e.g. calcium, magnesium, iron).
  • Nutrient rotation : Adapt the nutrient composition to the different growth phases of the plant (vegetative vs. flowering).

4. Ventilation and oxygen

  • Air stones and pumps : Use air stones and air pumps to oxygenate the nutrient solution. Oxygen deficiency can lead to root rot.
  • Root aeration : Ensure the roots are adequately aerated, especially in systems such as DWC or aeroponics.

5. Light

  • Lighting : Cannabis requires intense light, especially during the flowering phase. LED or HPS lamps are common.
  • Light cycles : Maintain a fixed light cycle: 18 hours of light and 6 hours of darkness for the vegetative phase and 12 hours of light and 12 hours of darkness for the flowering phase.

6. Temperature and humidity

  • Water temperature : Keep the nutrient solution temperature between 18-22°C to optimize oxygen solubility and nutrient uptake.
  • Air temperature : Ideal is 20-28°C during the light period and 15-20°C during the dark period.
  • Humidity : Keep the relative humidity at 40-60% during the vegetative phase and 40-50% during the flowering phase.

7. Cleaning and maintenance

  • System Cleaning : Clean the system regularly to prevent algae growth and nutrient buildup.
  • Water changes : Change the nutrient solution every 1-2 weeks to maintain nutrient concentration and quality.

8. Monitoring and adaptation

  • Monitoring : Use pH and EC meters to check and adjust the nutrient solution regularly.
  • Adaptation : Respond quickly to changes in plant physiology, such as yellow leaves (nutrient deficiency) or burnt tips (nutrient excess).

Conclusion

Growing cannabis hydroponically requires careful planning, monitoring, and maintenance. However, with the right equipment and attention, you can achieve healthy plants and high yields. Make sure you're well-informed about your plants' specific needs and prepared to continually adapt and optimize your methods and practices.