Definition - What does Damping Off mean?
Damping off, caused by fungal growth most often during the seedling stage, is a condition that affects all types of agricultural operations, including cannabis growing. In wet, cool conditions, pathogens are able to thrive in soil/growing media, and weaken seedlings immediately after germinating, leading to slow growth or even seedling death.
The first sign of damping off is usually a mushy stem and dropping leaves (which can be mimicked by many other conditions). Eventually, the stem will weaken and begin to topple over, and the leaves will die. This is followed by plant death.
Hydrolife explains Damping Off
Damping off is a condition that can affect any agriculturally grown crop, including cannabis plants. The term is in reference to the effects of a disease or attacker on the plant itself, rather than a description of the disease or problem itself.
Damping off strikes seedlings, although the aggressor can attack seeds before germination. It is most common in cool, moist growing conditions, such as a greenhouse without the right amount of light and temperature control. The most common aggressor is a fungus, with both Pythium and Rhizoctonia being known troublemakers.
Essentially, what occurs is the fungi will attack a seed, or a seedling’s roots. There, it creates a blockage that prevents the proper uptake of water and nutrients. Essentially, the plant is starved to death.
Once the process has started, there is nothing the grower can do to prevent damping off from killing the plant(s). This is because the plants are too young and not strong enough to withstand the fungus or a fungicide. However, the problem can be prevented by using a sterile growing medium rather than natural soil, by not overwatering, and by not over-fertilizing plants. All of these missteps can create an environment ripe for pathogens to thrive.