Important Factor #1. Heat will dry it out and too much moisture can cause dangerous bacteria to grow.
The excessive heat can dry out the cannabinoids and terpenes, and these oils are essential. Mildew and mold best thrive in temperatures between 77 and 86 degrees, so a basic precaution is to keep your cannabis in a cool, dark place. Warm air holds more moisture than cold air so keeping cannabis in the proper environment with proper levels of relative humidity (RH) is crucial in reduces the chances of mold. Generally, storing cannabis in a controlled environment with RH levels between 59% and 63% will reduce the chances of mold, and will help to maintain color, consistency, aroma, and flavor.
Important Factor #2. Air will dry it out and lessen its potency.
Storing your cannabis in a container with just the right amount of air is crucial to keeping it fresh and true to its original form. While having too little air can greatly affect the relative humidity, having too much air will expose the cannabinoids to oxygen and will then speed up the degradation process.
Important Factor #3. Light can be harmful to the trichomes (the sticky resin glands attached).
It has been show that light is the single biggest factor in the degradation of cannabinoids. Storing your cannabis out of direct light will also help you control the temperature. Harmful UV rays will degrade your cannabis over time.
Important Factor #4. Too much handling causes the trichomes to come off.
Rough handling can easily cause the trichomes to fall off, so be extra careful when handling your cannabis.