Cannabis, like many other plants, develops nodes and internodes throughout the growth cycle, which are important in understanding the overall health of your plant and are central to development in a way that suits your growing environment and yields the best results.
All plant stems are connected by nodes and internodes. Nodes are parts of a plant that link new stems to older ones, which can take the form of a branch, leaf, or even bud.
For example, in a cannabis plant, the nodes on the main stem are the areas where new branches separate from the main stem of the plant. They are also the area where bud flowers are born.
The node just below the main flower of the cannabis plant (sometimes called the “apex”) is called the apical meristem.
On the other hand, internodes are sections of the trunk / branch between two nodes. Cannabis strains, which are known to grow vigorously under favorable conditions, tend to have longer internodes than other varieties.
Why are these plant elements so important in cannabis life?
Nodes and internodes can tell you a lot about the field of your plants and whether they are exposed to the right temperature and the right amount of light. They also play an important role in pruning and cloning.
Plant gender
If you are unsure whether a plant is male or female, take a closer look at its nodes.
Plants usually begin to form flowers within 3-6 weeks in their vegetative phase. These flowers form at nodes along the meristem (central stem) of the plant and other branches and take one of two separate forms.
Flowers with long, white hairs pistils are the hallmarks of a female plant. Small, closed buds, on the other hand, are hallmarks of male plants.
Marijuana temperature and lighting
Finally, the distance and size of your plants’ nodes and internodes can tell you if you need to adjust temperature or lighting in your growing area.
If you notice that the internodes of your plants are growing too long / short, this could be a sign that they are experiencing too much temperature changes at night.
Warm nights and cold days tend to shorten the inter-site distances. On the other hand, warm days and cold nights can lead to an increase in internodes.
Unusually long internodes can also be a sign of a stretched plant. This happens when plants don’t get enough light and go out in search of the nearest light source.
Long internodes are problematic as they can develop into weak branches that, during flowering, can break under the weight of the plant’s buds. Shorter internodes will ensure that your branches are strong enough to support the weight of your plant’s buds as harvest time approaches.
Cannabis pruning
Knots and internodes are also important when pruning season comes.
After about 2–3 weeks of the growing cycle, inspect your plants to make sure they have a few large internodes before you start pruning and removing obscuring leaves to the side branches.
There are various ways to prune cannabis plants, and most of them require you to cut the plants at specific nodes.
For example, when topping, it is required to cut the meristem of the plant slightly above the node with thick strong branches. This allows your meristem to create two separate branches, which eventually form large and equally powerful tops.
Also, some pruning techniques encourage you to prune the meristem to leave only 4 main branches. This will concentrate growth in these areas and help develop thick, dense bud buds along these branches.
Some growers also swear by trimming the tips of the branches to stimulate a higher growth rate of the shoots just below the cut.
Whichever pruning method you choose, knots and internodes are vital to understanding where to make the right cuts to stimulate your plant to grow and develop efficiently.
Cloning cannabis plants
Cloning allows you to maintain a specific phenotype of a plant for years to come, which is great if you happen to grow a plant that exhibits exceptional traits.
Clones are usually cut from the lower parts of the plant as they produce stronger, healthier cuttings. Most breeders take their cuttings from branches at least three nodes from the top plant group to ensure optimal health for their clones. To take a clone from a mother plant, it is usually sufficient to cut a branch just above the node.