The way cannabis inhales and exhales
Every cannabis leaf has very tiny holes on the underside. To watch them you need a magnifying lens. But their function is vital. And if we understand the reason why they are in the leaves we will probably change certain methods to cultivate.
The stomata inhale CO2 and exhale water and oxygen. Ideally they should be open all the time. But when it is too hot and they haven’t been watered enough thy close in order to avoid lost of humidity. For this reason, many growers shade their weed with a little cover during the hottest hours of the day in summer. We all know cannabis is a sun plant. But doesn’t mean it loves too much heat. Cannabis suffers when the temperatures are too high and closing their stomata is the one way they have to prevent the lost of too much humidity.
Ideally, it is best for stomata to absorb as much CO2 as possible, to facilitate photosynthesis. However if they remain open for too long the lost of water will be a disaster. Therefore, it is a question of balance between the time they are open and closed. While they remain open they inhale CO2, which is very good. And when they are closed they don’t. But, at the same time, when stomata are closed the plant don’t lose humidity, which is good too. Since stomata must be either open or closed, the plant is constantly walking a razor’s edge between moisture loss and CO2 absorption. This balance depends on the environment and health.
How do they do their function?
Stomata are microscopic holes on the undersides of leaves. The hole is made up of twin guard cells and auxiliary cells.
The function of the guard cells is to allow the stomata to open and close depending on what the plant needs. The name of this process of absorption is named osmosis. It occurs when a liquid with less concentration of dissolved solids goes across a membrane to an area with a higher concentration of dissolved solids. The guard cells are in charge to build up dissolved solids so they can absorb water. They need potassium and sugars to do their job. Stomata remain open at day and closed at night.
CO2 and quantity of light
Too much external CO2 will lead to smaller stomata openings. This can produce an too much heat and the leaves turn yellow. Because of this airflow is important. Cooling the plant can help prevent this. CO2 levels of around 1500 ppm are excellent for a correct CO2 absorption.
Relationship between stomata and humidity
It is a question of balance between the internal levels of moisture and the humidity in the environment. This balance depends mostly on the quantity of water absorbed by the roots and the water evaporated through the leaves. If the plant is lacking water the stomata will close even though this affects the photosynthesis. But interrupting the photosynthesis process is better than a dead or weak plant. It is even worse than the lack of CO2 the incorrect temperature of the plant. The stomata are the way cannabis plants have to cool down their temperature. When the stomata are closed, the leaves get hotter, which causes further evaporation. It is a complex system that can be solved with a correct culture. If the plant is low in water, because we don’t water it enough, the stomata will close.
There are many factors to grow good marijuana plants. Understanding each one in very important to obtain good results.