🔍 Why are temperature and humidity so important?
Cannabis is a sensitive plant. Too much heat, cold, or humidity can lead to mold, nutrient deficiencies, growth stunting, or pest infestation . Therefore, anyone who wants consistently high-quality yields needs not only watering and fertilizing but also controlling the climate in the grow room.
🌿 The ideal temperature for growing cannabis
| Growth phase | Temperature day | Night temperature |
|---|---|---|
| germination | 22–26 °C | 20–22 °C |
| Vegetative phase | 22–28 °C | 18–22 °C |
| flowering phase | 20–26 °C | 16–20 °C |
Tip: Excessively high temperatures (>30°C) lead to heat stress. This causes leaves to curl, growth stagnates, and flower quality suffers.
💧 The ideal humidity
| Growth phase | humidity |
|---|---|
| germination | 70–80% |
| Vegetative phase | 50–70% |
| flowering phase | 40–50% |
| Late flowering (last 2 weeks) | 35–45% |
Caution: During the flowering phase , too much humidity is dangerous—there's a risk of mold growth in the buds. A dehumidifier can help.
🛠️ Tools & tips for control
- Thermo-Hygrometer : Affordable and indispensable – measures temperature & humidity
- Humidifier / dehumidifier : For a stable climate
- Supply & exhaust air systems : Regulate temperature & humidity
- Recirculation fans : Prevent humid, stagnant air & promote stable conditions
🚀 Bonus: VPD – The insider tip for advanced growers
Vapor Pressure Deficit (VPD) takes temperature AND humidity into account and helps you optimize plant transpiration. Those who use VPD can take growth and yield to a new level.
Conclusion
Good climate = good harvest. Keep your temperature and humidity levels within the optimal range, and your plants will thank you – with vigorous growth, dense buds, and a strong aroma. The correct use of climate technology can make all the difference!