Throughout the different stages of marijuana cultivation, plants may suffer from nutrient deficiencies and excesses, as well as blockages that will have a direct impact on crop quality.
Knowing how to identify them so that they can be treated in time, is essential to obtain a harvest of maximum quality and yield.
There are three types of nutrients that cannabis plants need:
- Macronutrients: they are essential for the correct development of plants and those that are needed in greater quantities.
- Secondary nutrients: They are also essential for the correct development of the plant and it requires them in large quantities.
- Trace elements or micronutrients: are essential for plant life as they are involved in photosynthesis and other vital functions. These types of nutrients are needed less.
MACRO-ELEMENTS
NITROGEN
Deficiencies:
-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 stalks.
It is important not to confuse yellowing and defoliation with the advanced flowering stage 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.
Excesses:
-Dark green leaves.
-Claw-shaped blades pointing downwards.
-Spiked plants with fragile and brittle stems and branches.
PHOSPHORUS
Deficiencies:
-Slower and weaker growth.
-Blue-green leaves.
-Purple-colored nerves.
-Darkest leaf tips and downwards.
-Leaves with necrosis (dark spots).
-Defoliation
Excesses:
Excess phosphorus is difficult to detect as it manifests itself by blocking the absorption of other nutrients such as calcium, magnesium, copper, iron and zinc and is very easily confused with a lack of any of these elements.
POTASSIUM
Deficiencies:
-Dark green colour of the leaves.
-Leaves with necrosis, especially in the lower part of the plant.
-The tips of the leaves are burned and curled up until they finally die.
-Weaker and more brittle branches.
-With a lack of potassium, plants are more prone to diseases and fungus.
Excesses:
As with phosphorus, an overfertilization of potassium is difficult to detect as it manifests 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.
SECONDARY ELEMENTS
MAGNESIUM
Deficiencies:
-Chlorosis (loss of green color) between the nerves of the leaves.
-Stains or yellow or brown spots on the leaves.
-The leaves are turned upwards.
-Defoliation.
Excesses:
-Blockage of other nutrients
CALCIUM
Deficiencies:
-Slow and weak growth of the plant.
-Yellow spots with brown edges on the leaves.
Excesses:
-Blockage of other nutrients
SULFUR
Deficiencies:
-Yellow leaves with green nerves.
-Petioles of the leaves with a purple tone.
MICRO-ELEMENTS
IRON
Deficiencies:
-General chlorosis of leaves. At first interventional and later general.
-Defoliation
Plants with stress are more likely to suffer from this type of deficiency.
Excesses:
-Widespread faint chlorosis
ZINC
Deficiencies:
-Chlorosis in the tips or between the nerves of the leaves.
-Slow growth
-Longer leaves and shorter internodal distance
-Leaf deformity
Excesses:
An excess of zinc could cause the plant to die because zinc has a high toxicity.
MANGANESE
Deficiencies:
-Slower growth
-Yellow leaves, start from the edge towards the center.
BORON
Deficiencies:
-Burns (brown spots) in new shoots
Excesses:
-Leaf necrosis
-Defoliation
MOLYBDENUM
Deficiencies:
-Interventional yellowing of leaves
-Necrosis and defoliation
-Inhibición de la floración
Excesses:
-Copper and zinc deficiency
COPPER
Deficiencies
-Necrosis in new outbreaks
-Chlorosis in leaves
CHLORINE
Deficiencies and excesses:
– Colour bronze on the leaves
It is very rare that there is a lack of chlorine in our plants because it is found in water and soil.
