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Fungus on Vegetable Plants

By Daniel Smith ; Updated September 21, 2017
Healthy vegetable plants will offer the most resistance to disease.
salad and vegetable plants growing in allotment image by scalesy from Fotolia.com

Vegetable diseases, such as fungi, can cause irreversible harm to plants and their crops. Fungi can sap a plant of all of its energy that is needed to grow vegetables. There are many different reasons for a diseased vegetable plant, but if the right steps are taken, gardeners can treat their sick plants or they can prevent fungi from occurring in the first place. If vegetable plants are given the proper care, they can fight diseases through the entire growing and harvesting season.


Downy mildew is a vegetable plant fungus that grows on stems and under plant leaves. Plants that are infected will turn purple or white in color. Another fungal disease is called “late blight,” and it commonly affects potato or tomato plants. Powdery mildew causes plants will turn white and the leaves will be coated with a powdery substance.


Fungal infections can affect plants for many reasons. Poor soil conditions, such as poor drainage, can leave plants waterlogged. Plants that are watered late in the day will have wet leaves overnight and this can encourage fungal growth and it can attract vegetable pests to attack. Plants that are sown too close to each other will not have room to allow air to circulate properly. Crops planted in same area as previously diseased plants will be infected unless the soil is sterilized or treated.


Vegetable plants infected with a fungal disease can die if it is not treated or removed to save nearby crops. Other effects of a fungal infection include wilted leaves, discolored or diseased crops, and misshapen vegetables.


Prevent fungus on vegetable plants by purchasing disease-resistant varieties. Some seeds that are not resistant may have a coating of fungicide that will protect the seed in the soil. Use proper spacing techniques to allow airflow. The amount of plant space depends on the type of vegetables in the garden. Water around the base of the plant and only water in the morning, as this will allow the plant to dry before nightfall.


Sterilize garden soil that contained infected plants. After the growing season ends, cover the diseased soil with a plastic tarp. The heat from the sun will kill off fungus and other plant diseases. Dusting with a fungicide can also save plants, if they are treated before the plant dies. Rotate crops every growing season because that which is deadly to one plant may not be dangerous to other plants.


About the Author


Daniel Smith graduated from technical school in 1993 and has been writing since 2005. His has written numerous articles for the instructional website called eHow in areas including gardening, home improvement, celebrating special events and health-related topics.