Sometimes the first sign of bud rot is a few leaves on the bud turning yellow. The nodes of these leaves are where the buds rot.
What causes sprouts to rot?
Cannabis bud rot is caused by a fungus called Botrytis cinerea. Botrytis cinerea can cause a variety of diseases. The specific symptoms are:
Onset at the seedling stage: mostly from the weakened cotyledon and the edge of the true leaf, the leaf becomes soft and drooping, and it is water-soaked at first, then it gradually turns pale brown to brown, nearly round, often with ring patterns, and the disease spreads along the petiole to the stem when the conditions are right. The stems appear water-soaked disease spots, causing the stems and leaves to rot and become thinner, and the gray mold layer grows on them, and the plants fall down in the later stage; sometimes the diseased parts develop rapidly in the longitudinal direction, and one side is damaged and collapsed. The spread of diseased and healthy seedlings caused the seedlings to rot in pieces. In severe cases, the dead seedlings could rot into a pool of mud.
Onset of adult plant stage: it can harm all parts of adult plant. The leaves generally start from the tip and the edge of the leaf, and are water-soaked at first, then the color becomes lighter and light brown; the diseased spots are not restricted by the leaf veins, and the rims are dense and easy to break. The diseased spots produce light gray and sparse mold when wet. The whole leaf can die.
Old leaves are more prone to disease, and diseased plants die from bottom to top. In addition, the diseased flower tendrils fall on the leaves, and the middle part of the diseased leaves has round to irregular shaped lesions, which are soaked in the first water, and then light brown with gray mold. Wounds caused by pruning and forks, broken stems and petioles can be an invading way, causing more serious losses. The disease develops towards stems, moss and cones, making them sunken and rotted. On cucumbers, tomatoes, eggplants, sweet peppers, strawberries, and sunflowers, the stems often die. After holding the stem, it sometimes breaks, causing the upper part of the plant to die. Because leguminous vegetables are lignified faster, they do not cause stems to break, only the skin rots, and the skin cracks and becomes fibrous when dry.
This pathogen often occurs during the flowering period of cannabis and when it is dried after harvest.
When a few leaves in the largest bud cluster suddenly turn yellow, it feels like it happened overnight. This may indicate that the nodes of these leaves have mold. Be sure to investigate all yellowed crowns as soon as possible. If there is mold, the leaves will fall, with mold or brown spots in the middle.
Botrytis looks white and fluffy at the initial stage. After the mold rapidly multiplies and begins to destroy, it will quickly turn black and shrink.
It will be harvested into the marijuana buds when it matures.
Fungal gray mold is sometimes called “black mold”, “fusarium wilt”, “bud rot”, “gray mold” or “gray mold”. In addition to cannabis bud rot, Botrytis can cause problems for many different types of plants, including wine grapes, strawberries and peonies.
How does Botrytis enter my plant?
Rotting spores are usually spread to plants through dusty gray spores in wind or water. If your plants have never touched these spores, they will never rot. But the spores have a strong ability to spread and survive, and it is difficult for cannabis to escape their roots. Whether you grow it outdoors or indoors, its spores will always spread around with wind and rain.
Although the spread of spores of Botrytis is difficult to control compared to non-professional growers, it is difficult for Botrytis to grow as long as you take good care of your plants.
Causes of the growth of Botrytis
- The growth of spores requires a warm and humid environment and stagnant air.
- High humidity (relative humidity above 55-60%) is the biggest cause of mold growth and bud rot
- Excessive contact of leaves forms a stagnant area for water.
- Stay in humid air continuously, such as staying in a rainy day for more than 5 hours, or being blown by the air in a rainy day.
- At night or cloudy days, there is too much dew on the plants and stays for too long.
- The cool air will also trigger the growth switch of Botrytis. Set the temperature as much as possible between 24 degrees Celsius and 28 degrees Celsius to avoid this situation.
- Lack of air circulation will also create conditions for the growth of Botrytis.
- A large number of dense branches and buds will store a lot of moisture inside the plant, and these uncirculated moisture will also become a breeding ground for botrytis. But most of the disease is due to too dense buds.
- Nutrient deficiency and lack of light can make plants weak and have poor tolerance and resistance, which can also cause an outbreak of Botrytis.
- For the infection of nearby plants, the spores of Botrytis spores will be spread with the air and rain. After the plant is infected, the nearby plants will also be infected in a short time.
- The varieties are too bad. Some varieties of hemp are easy to attract the patronage of Botrytis. Choosing a good variety is the core key to the whole planting process.
How to prevent rot and mold?
- The most important thing is to maintain humidity below 50%, which is the most important measure to prevent sprouts from rot and growth. Botrytis is rarely seen in dry conditions. If the humidity problem is not resolved, bud rot may continue to spread even if all affected buds are removed.
- Good air circulation creates good ventilation conditions and ensures that there is always plenty of air circulation on all buds and leaves. Make sure your plants have access to fresh air.
- Prevent large temperature fluctuations between day and night. Sudden temperature fluctuations will condense water vapor or stimulate plants, which will give bud rot a chance.
- Avoid small drops of water and try not to spray water on the flowering cannabis. If there is dew hanging on the flowering cannabis, shake her to prevent the plants from hanging water.
- Remove all moldy and rotting parts immediately. Once the plant begins to moldy and rotting, cut off this part and remove it, even if it is mildly moldy.
- Pay attention to the wound. Once a wound is left on the flowering cannabis, many fungi will make a fuss around the wound and cover the wound carefully with tape.
- Pay attention to the distance, leave enough distance between buds and buds, and leave enough distance between plants and plants.
- Remove the fallen leaves, don’t let the fallen leaves stay in the soil, this will breed various bacteria and fungi.
- It is often observed, often after the cannabis enters the flowering period, this is when the cannabis is relatively fragile.
What should I do after bud rot has occurred?
Once bud rot and mold have occurred, the rot and mold must be removed. If the symptoms are mild, you can spray the nearby areas and water the soil with a special fungicide.
If the mold is more serious, the moldy parts can only be harvested and dried in advance after removing the moldy parts. If the ventilation is insufficient or the humidity is too high, the parts that are dried will also be moldy.
Keeping dry and breathable is the most effective way to prevent moldy and rot. Although moldy and rot can cause great damage, it is still very simple to prevent it.