Mold for cannabis or for any other type of plant represents a great threat, both in indoor and outdoor cultivation, since when it becomes evident it is already too late to intervene.
Like any plant species, cannabis is often attacked by fungi and mold. Mold itself is a type of multicellular organism that contains various types of fungi with different taxonomy.
This sneaky enemy is greatly feared by every grower as it is capable of seriously compromising your harvest . Finding mold and rot on the buds of your grow can be really frustrating. For this reason it is very important to know how to immediately recognize the first signs and treat the plants peremptorily.
The purpose of this article is to find out what the most common types of marijuana mold are and how to prevent and treat them effectively.
Types of cannabis mold
In a marijuana plant, mold can appear throughout the growth cycle, therefore, both in the vegetative and flowering phases. But even after the harvest has taken place, in the drying and curing phase of the buds, there is the risk of seeing rot appear .
Furthermore, mold - like all fungi - produces spores that infest the air and, under the right humidity conditions, could attack and damage other "healthy" plants inside your grow room.
This is why we recommend, first of all, to always keep the cultivation environment clean and well ventilated, maintaining adequate heat and humidity conditions in balance, so as not to encourage the proliferation of mold.
As previously mentioned, there are different types of cannabis mold , some that attack the apical flowers, others on the leaves, but also in the root system. Below we will list only the most dangerous and frequent species in cannabis plants.
- Botrytis;
- Powdery mildew.
Let us therefore try to understand what their characteristics and distinctive signs are , to know how to prevent them and recognize them immediately if they arise.
Recognize the botryts also known as grey mud
BOTHRITIS IS LIKE DUST ON FURNITURE, YOU CAN LIMIT IT, BUT NEVER ELIMINATE IT COMPLETELY!
One of the most common and most feared plagues by growers, both in indoor and outdoor cultivation, is certainly botrytis . Since it is very difficult to detect it in the primordial stage, it can ruin part of the harvest in the final stages of flowering .
It is a very harmful aerobic fungus, capable of settling in the tissues of plants which rot due to certain enzymes which destroy plant cells
Its name derives from the fungus that causes it, namely Botrytis Cinerea , a pathogen that often attacks flowering and fruit plants. The Latin term "Cinerea" means "ash compost" and refers precisely to the typical gray color that this type of mold takes on on plants.
The climatic conditions favorable to the development of Botrytis are high levels of environmental humidity (80-90%) and high temperatures (above 28°C).
Botrytis is very difficult to identify because it begins to attack mainly the inside of the inflorescences, expanding outwards; It goes without saying that locating it in its primordial state is very difficult if we are not expert growers.
How does botrytis manifest itself in cannabis?
- Gray fuzz on the flower surface (early stage);
- little by little the flower becomes covered with a kind of "mud" (advanced stage);
- Buds, pistils, calyxes and leaves will change color, from green to grayish brown, and begin to dry and wilt.
Be careful, therefore, not to focus only on the superficial aspect of the flower, but look carefully inside it.
As mentioned, the fungus attacks starting from the stem, walking towards the outside of the tops . In this regard, the constant ability to observe the flower is essential.
How does Botrytis reproduce?
The reproduction of the pathogen in question occurs asexually through its conidiophores, species of thin branches.
They generally affect the aerial part of the plant, particularly those containing greater quantities of water and sugars, such as the apical inflorescences or fruits.
The plants are attacked by the spores released by the conidiophores, which will give rise to new generations of the fungus and therefore to the disease.
During the winter the fungus is preserved in the form of mycelium and is capable of resisting external agents. In older plants it forms sclerotia, i.e. corpuscles having the shape of small, black spheres, but visible to the naked eye, both on the tissues more external than internal.
With the arrival of spring and warmth (and the pollination period), the sclerotia develop the mycelium which will form the hyphae (mushroom filaments), causing the propagation of the fungus itself which will spread very rapidly.
Precisely due to its characteristic of adaptability to the environment in which it occurs, the fungus shows excellent resistance to fungicides or fungicides used for curative purposes.
How to fight and prevent cannabis botrytis?
The only truly effective way to combat cannabis botrytis is prevention and observation
High temperatures, excessive humidity and poor air circulation are the three conditions that favor the appearance of Botrytis . This means that in indoor cultivations and greenhouses it is essential to have air extractors and fans for correct air recirculation.
These tools help maintain a dry, temperate climate that prevents the fungus from reproducing and releasing spores into the air.
All this is decidedly more complicated for outdoor cultivation in the open field. So how can we prevent mold in outdoor cultivation?
Cleaning cutting tools is a good way to start, as is spacing plants appropriately to prevent excessive humidity levels.
However, the natural treatments listed below are definitely the most effective tools if used in a preventative and peremptory manner .
- As we well know, "prevention is better than cure", so to create a preventive barrier against fungi and mold, the use of the flavonoid extract of Propolis for plants is recommended .
- Horsetail, a medicinal plant rich in flavonoids, alkaloids and silicates that strengthens plant tissues, preventing fungal diseases;
- Rock dust, a substance of natural origin capable of improving the resistance of plants to biotic stress caused by pathogenic microorganisms;
- Tricoderma harzianum, a beneficial fungus that colonizes the roots but also the tissues of flowers if vaporized on them, which not only controls and inhibits the proliferation of other fungi, but helps the absorption of nutrients from the soil
- Copper , an essential micronutrient for plants and accepted in ORGANIC agriculture to keep harmful molds at bay;
- Organic sprays based on Bacillus Subtilis (Serenade), a species of soil bacteria with antifungal properties, effective against botrytis and powdery mildew.
- Kanaplant Defense 3, natural antifungal ideal for combating attacks of mold, fungi and hatred. 100% organic product based on Horsetail and Aloe Vera.
What if mold has already formed on the plant? In this case it will be necessary
- strictly eliminate the contaminated flower or bud.
- cut the affected leaves affected by mold;
- Sterilize and clean pruning tools immediately after use;
What if mold appears during the drying phase? Find out how to do it by reading the next paragraph.
- Create a sufficiently large and light-free drying area;
- Hang the buds upside down to facilitate slow and natural drying;
- Maintain a constant temperature between 16-22°C and a maximum humidity of 50-60%;
- Make sure that the room is ventilated or, better yet, adequately cooled with an air conditioner;
How to prevent powdery mildew
Cannabis taint , also known as white mite, appears on the foliage of plants as a layer of dust-like spores, before then spreading to the rest of the plant: branches, stems and even the flowers.
Odium infection is caused by a species of fungus that belongs to the Ascomycetes family. The name derives from the Latin "Oidium" which in ancient times referred to this particular species of mushroom.
Powdery mildew attacks almost all plant species, not only cannabis , but also many vegetable plants such as tomatoes as well as fruit trees, such as apple and pear trees.
It is above all the younger leaves that suffer from the aggressiveness of this mycotic infection. In the initial stage the infection manifests itself with a thin white fluff causing the leaves to curl upwards .
The affected leaves gradually begin to dry out and rot. This fungus works by inhibiting a plant's photosynthesis process. In this way, all natural sources of energy will be blocked, limiting the growth of the plant and - consequently - a drastic reduction in the harvest and production of buds.
But what are the signs that Powdery Mildew manifests itself and that you need to learn to recognise ?
- White, dust-like spots on leaves;
- Foliage distorted and with slow growth;
- Discoloration of foliage plant tissue.
- Small circular raised spots and black spores (advanced stage);
- Poor flowering.
Powdery mildew can also attack plants in both outdoor and indoor cannabis cultivation, but only in the presence of certain conditions, i.e. stagnant air and excessive humidity.
This is why it is essential to be able to adopt the right preventive cultivation strategies in order to have healthier crops capable of giving you lush buds.