Yellow Flowers in your crop and how to solve it

The first step is an accurate diagnosis

Why are yellow leaves damaging your cannabis crop? Chlorosis, in simple terms for common growers, involves a loss of chlorophyll. To treat it effectively, it is important to understand the problem before taking drastic measures. Don't jump to 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 on young plants. Correctly identifying the cause of the problem and acting quickly to fix it can help your marijuana recover.

Possible causes:


1) Lack or excess of watering One of the most common mistakes in cannabis cultivation is not providing the right amount of water at the right time. Cannabis plants need an effective watering cycle to thrive. How can you tell if your marijuana needs water? You can lift the pots when they are dry and then compare the weight with that of the freshly 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. Too much water can cause root rot, while too little water will limit growth. If you consider it necessary, keep a record in a cultivation diary and try to establish an appropriate routine as the cultivation progresses.

2) PH Growers using substrate benefit from growing in a medium that acts as a buffer for the roots. However, hydroponic and coconut systems are not as forgiving of pH imbalances. Even substrate growers should get closer to the ideal pH, which is between 6 and 7, to prevent their plants from suffering. A pH between 5.5 and 6.5 is generally considered to be the recommended range for hydroponic and coconut systems. If the leaves turn yellow, it may be a warning sign that you have not achieved a good fertilization balance and that the pH has drifted.

TREATMENT: Invest in a pH meter or specific fertilizers for cannabis that allow you to automatically adjust the pH within an ideal range. It is also important to wash the roots of the plants with clean water and restart fertilization using a light solution adapted to your growing medium. Also, make sure that the basic fertilizers you use contain all the essential microelements. If they don't, it will be necessary to add additional supplements to your budget.

3) Deficiencies and light burns
For indoor cannabis plants grown under artificial light, it is crucial to ensure that they are positioned correctly and that the lamps are at the appropriate distance from the canopies to obtain satisfactory results. If spotlights and reflectors are too close to the upper parts of the plant, such as the apical colas, buds and leaves may turn yellow and brown due to excessive light intensity. This problem mainly affects the upper parts of the plant and spreads downwards.



TREATMENT: Be sure to hang your grow lights according to the instructions provided by the manufacturer. As the plant develops, adjust the height of the lights and use a tape measure to achieve this precisely. There are various grow light technologies on the market today, each with its own specific characteristics, so it is advisable to follow the manufacturer's instructions to place the lights in the optimal spot.

4) Septoriosis
Septoria usually appears during the early stages of the flowering phase. If left untreated, this pathogen can destroy many leaves.

TREATMENT: First of all, it is necessary to remove infected leaves. Disinfect your pruning shears and carefully cut off any leaves that show signs of septoria. Removing infected fan leaves will help prevent the spread of the disease. As the next step in the treatment, perform a foliar spray with neem oil to eliminate any invisible traces of the pathogen. Additionally, it is important to clean the base of your plants. Remove any dead leaves that may be carrying spores and add a new layer of mulch to prevent spores from entering the soil.


5) Heat waves

Heat waves can cause yellowing and dryness of marijuana leaves, both in indoor and outdoor crops. When temperatures exceed 28ºC, plants cannot carry out photosynthesis efficiently, resulting in buds that are less dense in their structure.

TREATMENT: Indoor growers will need to use air conditioning to keep temperatures under control, and it is important to ensure that the intake and exhaust fans are appropriate for the size of the grow room. It is recommended to check the specifications and performance of the fans on the manufacturer's website. For outdoor growers, the best thing to do is build a shade structure and hope the heat wave passes soon.


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