Why Do Outdoor Plants Get Fungus?

Outdoor plants are exposed to a variety of environmental conditions, including temperatures and humidity that can contribute to the growth of fungus. Fungus is a type of microorganism that has the ability to cause damage to plants by reducing their overall health and vigor.

The type of fungus, as well as the severity of the infection, will depend on the environmental conditions in which it is growing.

Fungus most commonly appears on outdoor plants during periods of excessive moisture. When soil and foliage become saturated with water, it creates an ideal environment for fungi to thrive.

Fungus spores are easily spread by wind, rain, and even people or animals touching infected areas. Once these spores have taken hold they begin to feed on plant matter, disrupting the plant’s natural growth cycle.

Fungal infections can also be caused by poor air circulation around a plant. When air flow is restricted, moisture builds up on foliage and provides a perfect breeding ground for fungal spores. High temperatures can also contribute to fungal infections because they promote rapid germination and growth of existing fungal colonies.

In addition to temperature and humidity levels, certain nutrients in the soil can also promote fungal growth. When soil is overly rich in nitrogen or phosphorus, it can create an environment where fungus thrives. If a plant is lacking in essential nutrients such as calcium and magnesium, this can also reduce its resistance to fungal infections.


The development of fungus on outdoor plants can be attributed to many factors such as high temperatures and humidity levels combined with low air circulation or soil nutrient deficiencies. Understanding what environmental conditions cause fungus growth is essential for preventing fungal infections from occurring or worsening in outdoor plants.

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Chris Powell