- 1). Plant your tomatoes in the best possible location to reduce the odds of developing a fungal disease. Tomatoes perform best in a sunny location with well-drained soil and space between the plants to allow good air circulation.
- 2). Rotate tomato crop placement in the garden, planting tomatoes in a particular area only once every three years or more, suggests the Missouri Botanical Garden experts. Plant vegetables with greater tolerance to fungal diseases in this area during the other years. This practice proves especially important if your tomatoes succumb to some type of fungal disease. Many fungi, such as Fusarium oxysporum, continue living in the soil for years after infected plants have been removed.
- 3). Control moisture levels on and around your tomatoes. Excessive watering, in addition to poorly draining soil, encourages root rot. Avoid watering with a sprinkler, and instead provide moisture to the roots. Mulch around your plants to encourage a constant moisture level.
- 4). Control insects and weeds, both of which potentially spread diseases from one source to another. Cage or stalk tomatoes to keep them away from possible sources of fungal infection, such as weeds growing in the soil around the plant. Use insecticides or herbicides if necessary to keep tomatoes free of fungal disease-carrying pests.
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