Temperature and humidity level are the two most essential factors that determine a lot about the health and yield of marijuana crops. Higher or lower, they can damage the crops and attract pests and fungus. Quite clearly, if you want a successful cultivation year, you need to be very careful about creating ideal weather conditions when growing cannabis indoors.
When talking about humidity, it’s relative humidity that you should be thinking about in marijuana cultivation. The relative humidity is calculated by the ratio of partial and complete pressure of water vapor at the same room temperature.
For successful cultivation, your indoor garden should have more cool air on a comparison with warm air. Why? Well, warm air has more water vapor, and extra water can make the conditions extremely humid, that, eventually, ends up in festering fungus, and the plant dies.
Moving on, the ideal humidity level in indoor marijuana cultivation depends upon the growth stages of the cannabis plant – seedling stage, vegetation stage, flowering stage, and late flowering stage.
1. Seedling Stage
During the seedling stage, the roots of indoor cannabis aren’t very strong. Thus, they need more humidity to make up for the requirement of water.
The ideal amount of humidity level for the seedling stage should be between 65-70% at the regulated temperature between 20-25° C for proper seedling growth.
With every passing week, the roots of the seedling become stronger. So, ideally, about 5% of humidity should be reduced/week until the flowering stage arrives. Anything between 40-70%, depending upon the strain and soil conditions, is just fine for optimum growth.
3. Flowering Stage
The roots have become stronger by the flowering stage. Thus, the humidity level shouldn’t be high. Ideally, it should be lower than 40% and the temperature should be low as well, not more than 26° C and nothing less than 20° C.
4. Late Flowering Stage
The late flowering period is 1-2 weeks right before harvesting the yield. The humidity level at this stage should range between 30-40 %. Also, temperature makes a difference. The day temperature (with lights on) should be between 18-24° C and the night temperature (with lights off) should be between minus 5-10° C.
On a closing note, it’s necessary that the growers should be well aware of the techniques of adjusting the temperature and humidity during indoor cultivation of marijuana.