Throughout the different phases of marijuana cultivation, the plants can suffer from nutrient deficiencies and excesses, as well as blockages that will directly affect the quality of the harvest.
Knowing how to identify them to be able to treat them in time is essential to obtain a harvest of the highest quality and yield.
exist three types of nutrients that cannabis plants need:
- Macronutrients: they are essential for a correct development of the plants and those that are needed in greater quantity.
- Secondary nutrients: they are also essential for a correct development of the plant and it requires them in great quantity.
- Trace elements or micronutrients: they are fundamental for the life of the plants since they take part in the photosynthesis and other vital functions. These types of nutrients are needed in less quantity.
- Slower growth, loss of vigor.
- Yellowing of the oldest leaves and the lower part that spreads throughout the plant.
- Defoliation or loss of leaves.
- Red stems.
It is important do not mistake yellowing and defoliation with the advanced phase of flowering in which it is normal for this to happen.
Plants need more nitrogen in the growth phase and it is more common for this deficiency to occur during this phase.
- Dark green leaves.
- Claw-shaped blades pointing downward.
- Spiky plants with fragile and brittle stems and branches.
- Slower and weaker growth.
- Blue-green leaves.
- Purple nerves.
- Leaf tips darker and downward.
- Leaves with necrosis (dark spots).
The excess phosphorus is difficult to detect since it is manifested by blocking the absorption of other nutrients such as calcium, magnesium, copper, iron and zinc and it is very easy to cause confusion with a lack of any of these elements.
- Dark green color of the leaves.
- Leaves with necrosis, especially in the lower part of the plant.
- The tips of the leaves burn and curl upward until they finally die.
- Weaker and more brittle branches.
With a lack of potassium, plants are more prone to diseases and fungi.
As with phosphorus, an overfertilization of potassium is difficult to detect since it is manifested by blocking the absorption of other nutrients such as iron, magnesium, manganese and zinc, and can be confused with a lack of any of these nutrients.
- Chlorosis (loss of green color) between the nerves of the leaves.
- Yellow or brown spots or specks on the leaves.
- The blades are turned upwards.
- Blocking other nutrients
- Slow and weak plant growth.
- Yellow spots with brown edges on the leaves.
- Blocking other nutrients
- Yellow leaves with green veins.
- Petioles of the leaves with a purple hue.
- General chlorosis of the leaves. At first interveinal and later general.
Plants with stress are more likely to suffer from this type of deficiency.
- Generalized mild chlorosis
- Chlorosis at the tips or between the nerves of the leaves.
- Slow growth
- Longer blades and shorter internodal distance
- Leaf deformity
An excess of zinc could cause plant death since zinc has a high toxicity.
- Slower growth
- Yellow leaves, starting from the edge towards the center.
- Burns (brown spots) on new shoots
- Leaf necrosis
- Interveinal yellowing of the leaves
- Necrosis and defoliation
- Bloom inhibition
- Necrosis in new shoots
- Leaf chlorosis
Lack and excess:
- Bronze color on the leaves
It is very rare that there is a lack of chlorine in our plants since it is found in water and in the land.