The first step is a successful diagnosis
Why are yellow leaves damaging your cannabis cultivation? Chlorosis, in simple terms for common growers, implies a loss of chlorophyll. To treat it effectively, it is important to understand the problem before taking drastic measures. Do not hurry to draw conclusions or panic. The leaves of your cannabis plants are like biological solar panels, they are essential for photosynthesis. It is not recommended to remove all yellow leaves, especially in young plants. To correctly identify the cause of the problem and act quickly to solve it can help your marijuana recover.
Possible causes:
1) Lack or excess irrigation One of the most frequent errors in cannabis cultivation is not to provide the appropriate amount of water at the right time. Cannabis plants need an effective irrigation cycle to prosper. How can you know if your marijuana needs water? You can lift the pots when they are dry and then compare the weight with that of the newly watered pots to notice the difference.
TREATMENT: Carefully observe the behavior of the plant after watering. Use one of the techniques mentioned to determine when to water and avoid possible relapses. An excess of water can cause rot of roots, while a lack of water will limit growth. If you consider it necessary, keep a record in a cultivation diary and try to establish an adequate routine as the crop progresses.
2) PH Cultivators who use substrate benefit when growing in a medium that acts as a shock absorber for roots. However, hydroponic and coconut systems are not so indulgent with pH imbalances. Even substrate growers should approach the ideal pH, which is between 6 and 7, to prevent their plants from suffering. In general, a pH between 5.5 and 6.5 is the recommended range for hydroponic and coconut systems. If the leaves become yellow, it can be a warning sign that you have not achieved a good fertilization balance and that the pH has diverted.
TREATMENT: Invest in a pH meter or in specific fertilizers for cannabis that allow automatically adjusting the pH within an ideal range. It is also important to wash the roots of plants with clean water and restart fertilization using a light solution adapted to your culture medium. In addition, make sure that the basic fertilizers you use contain all essential microelements. In case they do not, it will be necessary to add additional supplements to your budget.
3) Light and burns
In the case of indoor cannabis plants that grow under artificial light, it is crucial to ensure that they are placed correctly and that the lamps are at the right distance of the glasses to obtain satisfactory results. If the spotlights and reflectors are too close to the upper parts of the plant, such as apical tails, buds and leaves can become yellow and brown due to excessive intensity of light. This problem mainly affects the upper parts of the plant and spreads down.
TREATMENT: Be sure to hang your cultivation lights according to the instructions provided by the manufacturer. As the plant develops, adjust the height of the lights and uses a tape measure to achieve it precisely. Currently, there are various culture light technologies in the market, each with its own specific characteristics, so it is advisable to follow the manufacturer's instructions to place the lights at the optimal point.
4) Septoriosis
Septoriosis usually appears during the early stages of the flowering phase. If not, this pathogen can destroy many leaves.
TREATMENT: First, it is necessary to eliminate infected leaves. Disinfect your pruning scissors and carefully cut any sheet that shows signs of septoriosis. Eliminating infected fan sheets will help prevent the spread of the disease. As the next step in the treatment, it performs a foliar spray with Neem oil to eliminate any non -visible pathogen trace. In addition, it is important to clean the base of your plants. Eliminates dead leaves that may be transporting spores and adds a new layer of padding to prevent spores from penetrating on the ground.
5) Heat waves
Heat waves can cause yellowing and dryness of marijuana leaves, both in interior and outdoor crops. When temperatures exceed 28ºC, plants cannot perform photosynthesis efficiently, resulting in less dense cogollos in their structure.
TREATMENT: Interior growers must use the air conditioning to maintain temperatures under control, and it is important to ensure that the entry and exit fans are suitable for the size of the cultivation room. It is recommended to consult the specifications and performance of the fans on the manufacturer's website. In the case of outdoor growers, the best thing they can do is build a structure that provides shadow and expect the heat wave to pass soon.
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