Here are some techniques that can effectively prevent or destroy it
Le Botrytis cinerea is a species of necrotrophic fungi of the family Sclerotiniaceae, division Ascomycota. Also known as gray mold, botrytis is a fungus that can attack your cannabis plants. As difficult to combat as it may seem, there are certain techniques that can prevent or destroy it effectively. This fungus likes hot, humid environments and uses other animals, such as caterpillars, to move around and reach cannabis plants. It is also extremely contagious. If you discover any infected plants, separate them from the rest as soon as possible to avoid further damage.
Botrytis is a parasitic fungus that can attack your cannabis plants at any time. It is important to know that certain conditions favor its proliferation and development: high humidity, sudden changes in temperature or heavy rains.
Everyone knows that the flowering phase is the most delicate time because infected plants at this stage can suffer irreparable damage. Besides weather conditions, there are other things that can greatly increase the likelihood that your plants will be affected by botrytis mold, for example caterpillars (their droppings can be a possible source of infection). Although the botrytis fungus is particularly difficult to fight off, knowing how to act preventatively or how to react when it's already set up could help you kill it for good.
Botrytis or gray mold is one of the most common fungi in cannabis plants. It normally grows in dead plant material on the ground. The spawn is the vegetative part of the fungus which is found in plant debris and which allows the absorption of nutrients. It is on these debris that the fungus can easily grow when the temperature and humidity levels increase, making late spring the perfect time for its appearance, although it can also appear in the fall. due to increased precipitation
In broad daylight, the vegetative mycelia begin to produce conidiophores with clusters of conidia which are then released and carried by air currents until they reach the stems and leaves. Botrytis cinerea conidia are asexually produced spores that can remain alive for years until conditions are favorable for their new development.
How to prevent
The best way to fight this fungus is to prevent it. Keeping your crop clean is essential to prevent botrytis from appearing (this includes anything that comes in contact with your plants). If the infection has already set in, you can prevent it from spreading by making sure that healthy plants do not come in contact with plants that you think may be infected. Their proximity facilitates infection from the air: if a spore settles on your plants, it is very likely that they will eventually become infected.
Keep your cannabis culture clean, including your tools
Making sure the area where you grow your plants is 100% clean is the best way to prevent the attack of the dreaded gray mold. The tools you use should be properly sterilized, including scissors, stakes, tags, etc. Also, wear latex gloves when handling the plants and try not to rub them with clothes that have been worn in other areas. You should avoid touching the buds because the fungus can be carried by the air but also with the help of your hands. Remember to carefully remove the infected parts.
Keep the tracks away
It is very important to keep insects at bay, especially caterpillars, as the cuticles of plants can be damaged by their bites, which makes it easier for the fungus to enter inside. Take preventative measures during the summer to prevent this from happening. Thus, you will limit their presence during flowering.
A major problem for cannabis growers is to identify the infection at an early stage because the buds do not appear to be affected. One of the most obvious indicators is necrosis on the stems, leaves and branches, which makes the tissue brown and moist. Another symptom indicating the presence of botrytis is the appearance of lighter circles on the buds, with a dark brown ring around them.
How to eradicate it
If you suspect that gray mold has already settled on your plants, the best solution is to remove all affected parts immediately. To do this, be sure to always use sterilized tools. If you decide to get rid of some buds, it is also best to cut at least three centimeters below. Then destroy all infected areas.
How to fight botrytis indoors
If you are growing indoors, ensure good air circulation and closely monitor the irrigation schedule. This will ensure that the humidity level remains low, which is essential for the well-being of the leaves and flowers. Never let the humidity level exceed 50%.
But do not think that the dangers will be over after harvest, because your flowers will still be in danger for a long time. During the drying phase, it is essential to maintain a humidity level below 60% and to ensure that the area is well ventilated. The best way to do this is to install a small extractor fitted with a carbon filter that maintains proper air and humidity levels.
How to fight botrytis outdoors
Two things make outdoor crops more susceptible to botrytis attack: rainfall and the fact that plants can develop a very dense canopy. In summer, when the plants are still growing and the flowers have not reached maturity, they are unlikely to be attacked by this fungus. However, it is during the late stages of flowering, in late summer or early fall, that the weather begins to change and rain becomes more frequent, resulting in poor circulation and excessively high humidity levels.
Pruning is also highly recommended as botrytis mold likes dense, bushy plants. Likewise, one can look for a cultivation method that allows to leave larger spaces between the plants and teaches them to grow so that they do not get too thick.
What to do with infected plants
If the preventive action does not work, you can always use Neem oil, an antifungal solution which is very useful for fighting infections caused by downy mildew, powdery mildew, botrytis, etc. Plant protection products are also very effective. The market is full of options; you just need to choose the one that best meets your needs. You should be fully aware of the risks of this infectious fungus and decide on the products and intensity of treatment accordingly.
It is also crucial to alternate different products so that the fungi do not get used to them and therefore become more resistant instead of dying. If the problem persists, try to repeat the treatment every week, increasing the frequency if you feel it necessary.
In any case, the infected buds should not be eaten under any circumstances as they can lead to lung problems, and in addition, the taste of the moldy herb is quite unpleasant and leaves something to be desired.