When it comes to cultivating and preserving high-quality cannabis, humidity control is one of the most critical factors. Whether you’re growing cannabis indoors, drying cannabis, or storing your harvested buds, maintaining the optimal cannabis humidity levels will directly impact potency, aroma, and overall quality.
In this guide, we’ll break down the ideal humidity and cannabis temperature conditions for both growing and storing cannabis. We’ll also explore fine-tuning these conditions to maximize yields and preserve cannabinoids and terpenes for long-term storage.
The Relationship Between Humidity and Temperature
Humidity and temperature are interconnected. Warmer air holds more moisture, while cooler air retains less. This is why cannabis growers must monitor both factors carefully to avoid mold, mildew, or overly dry buds.
Humidity is typically measured as relative humidity (RH), which represents the moisture percentage in the air relative to what it can hold at a given temperature.
For growing cannabis, humidity levels must be adjusted throughout the plant’s life cycle. Meanwhile, for storing cannabis, RH levels must be precisely controlled to maintain freshness and prevent degradation.
Best Humidity for Growing Cannabis
Throughout its life cycle, cannabis requires different humidity levels to thrive. Here’s a stage-by-stage breakdown:
1. Seedling Stage (65-70% RH)
- Young cannabis plants rely on humidity to absorb moisture through their leaves since their root systems are still developing.
- Ideal temperature: 20-25°C (68-77°F)
- Keeping humidity high ensures seedlings don’t dry out.
- Use a humidity dome to maintain stable moisture levels.
2. Vegetative Stage (40-70% RH)
- As cannabis plants mature, roots become more efficient, requiring less environmental humidity.
- Reduce RH levels gradually by 5% each week.
- Ideal temperature: 22-28°C (72-82°F)
- Increase air circulation to prevent mold growth.
3. Flowering Stage (40-50% RH)
- Lowering humidity in this stage is crucial to avoid bud rot and fungal infections.
- Ideal temperature: 20-26°C (68-79°F)
- Good airflow and dehumidification are key.
4. Late Flowering / Pre-Harvest (30-40% RH)
- Reducing humidity further helps maximize resin production and trichome development.
- Ideal temperature: 18-24°C (64-75°F)
- Lowering night temperatures by 5-10°C can enhance terpene preservation.
Pro Tip: Investing in a hygrometer to monitor RH levels is essential for successful cannabis cultivation.
Best Humidity for Storing Cannabis
Once cannabis is harvested and dried, it must be stored under precise conditions to maintain potency and flavour.
Ideal Storage Humidity (55-65% RH)
- Keeping cannabis between 55-65% RH prevents mold while preserving essential terpenes and cannabinoids.
- Lower than 55% can cause the buds to dry out and lose potency.
- Higher than 65% can promote mold growth.
Best Storage Temperature (15-21°C / 59-70°F)
- Cannabis should be stored in a cool, dark place to prevent degradation.
- Excessive heat can accelerate cannabinoid breakdown, reducing potency.
How to Maintain Proper Humidity in Storage
- Use humidity control packs like Boveda 62% to maintain consistent RH inside jars.
- Store cannabis in airtight glass jars or the official Boveda cannabis container to prevent fluctuations in moisture levels.
- Keep stored cannabis away from direct sunlight and heat sources.
- Avoid plastic bags as they can create static and degrade trichomes.
How to Adjust Humidity for Growing and Storing Cannabis
How to Lower Humidity
- Increase airflow with fans and exhaust systems.
- Use a dehumidifier to remove excess moisture.
- Water plants right after lights turn on to prevent excess evaporation.
- Run lights at night when temperatures are cooler.
How to Raise Humidity
- Use a humidifier or place water trays in the grow room.
- Mist plants lightly (only during the vegetative stage).
- Keep the grow tent sealed to retain moisture.
- Increase plant density to raise RH levels naturally.
How to Adjust Storage Humidity
- If buds are too dry, add a humidity pack (e.g., Boveda 62% or Integra Boost).
- If buds are too moist, open the jar slightly for a few hours.
- Regularly check RH levels inside storage jars using a digital hygrometer.
Conclusion
Mastering cannabis humidity and cannabis temperature is essential for both growing and storing cannabis. Maintaining optimal RH levels during cultivation ensures healthy growth, while proper storage conditions preserve flavour, potency, and quality.
Whether you’re a cultivator aiming for high yields or a connoisseur looking to preserve your stash, dialling in the perfect humidity will elevate your cannabis experience.
