Control of leaf spot diseases in cannabis

## Introduction

Leaf spot diseases, caused by various fungi and bacteria, are a common problem in cannabis cultivation. They manifest themselves as various types of spots on the leaves, which can impair photosynthetic performance and, in the worst cases, weaken the plants.

## Recognize symptoms

The first signs of leaf spot disease are small, round or irregular spots on the leaves, which can be yellow, brown or black. As the disease progresses, the spots enlarge and may join together. If leaf spot disease is suspected, a close examination of the leaves should be carried out to identify the specific cause.

## Check environmental conditions

Leaf spot diseases often develop in high humidity and inadequate ventilation. By controlling the environmental conditions, the risk of infection can be reduced. A humidity of 40-50% during the flowering phase and good air circulation are crucial to prevent the development of these diseases.

## Use biological control

Various methods can be used for biological control. The introduction of beneficial organisms that control pathogenic fungi, such as certain Bacillus strains, can be helpful. Spraying plant extracts, such as garlic or neem oil, can also curb the spread of the disease.

## Use chemical agents

If biological methods are not sufficient, chemical fungicides can be considered. It is important to choose products that are specifically approved for use on edible plants. Strict adherence to the application instructions is essential to avoid residues in the flowers. Fungicides should ideally be applied in the early stages of the disease to prevent spread.

## Prevention

Preventative measures are the best protection against leaf spot diseases. This includes regularly inspecting plants for early signs of disease, ensuring good air circulation and avoiding over-watering. Furthermore, tools and hands should always be kept sterile when handling plants to prevent the transmission of pathogens.

## Pro Tips

- Carry out regular leaf inspections

- Check humidity

- Keep tools sterile

- Introducing beneficial insects

- Use fungicides correctly