Homemade Fungicide for Tomatoes

Baking Soda Fungicide

• Baking soda is a white, soluble kitchen staple often used as a fungicide on plants. Mix 4 teaspoons baking soda and 1 teaspoon horticultural oil, citrus oil or molasses into 1 gallon of water. Shake it up well until the baking soda dissolves. Put this mixture into a spray bottle and spray it onto any parts of the tomato plant affected by fungal symptoms such as mildew, black spot or brown patch. If you don't have baking soda, potassium carbonate -- also known as baking powder -- is a good substitute.

Cornmeal Fungicide

• Cornmeal is another common kitchen ingredient that serves as a tomato fungicide. Due to natural anti-fungal properties, cornmeal can be used to create a fungal-fighting solution when mixed with water. To make a cornmeal-based spray, soak 1 cup of cornmeal in 5 cups of water for an hour, or until the water looks opaque and milky. Strain the solid cornmeal out of the solution, then put it in your sprayer. Spray the resulting milky liquid onto your tomato plants.

Vinegar Fungicide

• Common vinegars found in most kitchens have effective anti-fungal properties for plants. To make a vinegar fungicide for tomatoes, dilute 3 to 4 tablespoons of vinegar in 1 gallon of water and spray the mixture onto your tomato plants. Apple cider vinegar can be used, but white vinegar is more effective in battling fungal problems on tomatoes.

Compost Tea

• Compost tea is a solution made by soaking compost in water. It gets its name from the iced-tea color of the liquid that results. To make compost tea, fill a bucket with equal parts compost and water. Let this mixture percolate for 10 to 14 days, and then strain out the solids. Dilute the solution in water until it becomes thin enough to spray. Apply the mixture to the foliage of your tomato plants, especially where fungus is visible.