Growing cannabis outdoors has several distinct advantages over growing cannabis in an artificial environment. However, there is one big drawback – plants in the open field are more susceptible to diseases than those that grow indoors. What are the most common outdoor cannabis diseases and how to prevent them? Why do plants get sick more often in the open field than in an artificially created environment? Choose and use 150 watt led grow light.
Briefly about growing marijuana outdoors
One of the undeniable advantages of outdoor growing is that there is no need to create conditions as close to natural as possible. If the necessary conditions for good growth and harvest can be created with the help of correctly selected components (coconut substrate, hemp fertilizers, a clear watering schedule, etc.), then it is impossible to completely recreate the light cycle inherent in an open environment, and perfect air circulation. Outdoor cultivation increases both the yield and the quality of the crop itself.
However, there is an undeniable drawback: outdoor plants are more susceptible to disease than indoor cannabis. However, with proper prevention, troubles such as disease and plant death can be avoided.
Cannabis diseases outdoors: varieties and causes
The diseases most commonly affected by outdoor cannabis are fungal, bacterial, and viral. The reasons for their appearance are the following factors:
- high humidity in combination with low temperatures;
- the presence of a fungus or infection in the soil;
- insufficient amount of light;
- nearby infected plants;
- transfer of the pathogen by insects or garden tools;
- the entry of the pathogen into the plant due to mechanical damage (scrapping, scratch, etc.).
The most common diseases of outdoor marijuana are:
- gray mold,
- white mold,
- powdery mildew.
Gray mold (or gray mold) is a bacterial disease. Most often occurs as a result of over-watering. A decrease in temperature is a favorable factor for development. The disease affects all parts of the plant except the root system. The visual image is dark gray oozing areas with a bloom and dark spots appearing nearby. The affected parts of the plant, be it the inflorescence, leaves or stem, begin to rot. To stop the development of the disease, it is necessary to reduce the amount of watering and spray the infected bushes with Bordeaux liquid. If it was not possible to cure sick plants, it is better to destroy them so as not to infect healthy neighboring bushes.
White rot (aka white mold) is one of the most common fungal diseases in cannabis. Unlike gray mold, it affects not only leaves and inflorescences, but also the root system. The main symptom of the disease is that a weeping spot appears near the root, the leaves begin to turn yellow and wither, and a white bloom resembling moss appears on the inflorescences. If the disease did not have time to infect the entire bush, you need to buy fertilizers (fungicidal substances), reduce the number of waterings, or use a copper-soap solution. But experienced growers recommend that beginners destroy infected bushes in order to avoid spreading the disease and infecting healthy neighboring plants.
This disease manifests itself as a white coating on the leaves and inflorescences, reminiscent of flour or powdered sugar. In the last stages of the disease, the leaves begin to dry out and fall off. The cause of the disease is often a large contrast of humidity (over 80%) and temperature (below 15 degrees). This is mainly due to prolonged rains or short-term showers, which carry a temperature drop. If a disease is detected, it is necessary to buy soil mixtures and replace the top layer of the soil with them, as well as reduce watering and spray the plants with fungicidal substances.