RH (relative humidity) is the percentage of water vapour present in the air compared to the maximum amount the air can hold at a given temperature.
Also called / Category:
Humidity / Environment, Media & Nutrition
Key takeaways:
- RH affects plant growth and development.
- Optimal RH levels vary for different growth stages.
- Maintaining proper RH can prevent plant diseases.
- RH is crucial for curing and storing cannabis.
What it is / How it shows up:
RH (relative humidity) is a term commonly seen in grow guides, environmental controls, and product storage instructions. It plays a critical role in the growth and health of cannabis plants. High RH levels can lead to mould and mildew, while low levels can cause plant stress. Growers often monitor RH to ensure an ideal environment, adjusting ventilation and using humidifiers or dehumidifiers as needed. RH is also important during the curing process, as improper humidity can affect the quality and flavour of cannabis.
How it’s measured or identified:
- Hygrometers measure RH in grow rooms.
- Environmental control systems display RH levels.
- Data loggers track RH changes over time.
Use in context:
- "The RH in the grow room should be around 60% for vegetative growth."
- "During curing, aim for an RH of 55-65% to preserve offset-4 transition-colors hover:underline" title="Learn more about Terpenes">terpenes."
- "Adjusting RH can help prevent powdery mildew."
Safety & compliance in Canada:
- Licensed producers must monitor and control RH in cultivation facilities.
- Health Canada provides guidelines for optimal RH in cannabis storage.
Related terms / See also:
FAQs:
What is the ideal RH for cannabis growth? The ideal RH varies: 70-80% for seedlings, 50-60% for vegetative growth, and 40-50% for flowering.
How does RH affect cannabis curing? Proper RH during curing, around 55-65%, helps preserve cannabinoids and terpenes, affecting flavour and potency.
Can RH impact cannabis storage? Yes, RH levels between 59-63% are recommended to keep cannabis fresh and prevent mould.
Sources:
- Health Canada
- PubChem