Causes of Fungus on Potatoes
The appearance of potato fungus happens mainly due to infected seed potatoes or planting in infected soil. Most potato fungi not only attack potatoes, but can survive (though may not kill) on other plants in the nightshade family such as tomatoes and peppers.
Using Potato Fungicides to Control Fungus on Potatoes
An excellent way to prevent blight fungus on your potatoes is to treat your seed potatoes with a fungicide before you plant them. Though there are many potato specific fungicides available in the gardening market, in actuality, most general fungicides will work just as well. After you have cut up your seed potato, thoroughly coat each piece in the fungicide. This will help to kill any potato fungus that may be on the seed potato pieces. You will also want to treat the soil that you will be planting the potatoes in, especially if you’ve had fungus problems on potatoes in the past or have previously grown other members of the nightshade family (which may carry potato fungus) in that spot. To treat the soil, pour fungicide evenly over the area and mix it into the soil.
Making Homemade Fungicide for Seed Potatoes
Below you’ll find a homemade fungicide recipe. This potato fungicide will be effective against weaker potato fungi, but may not be as effective against more resistant strains of late potato blight.
Homemade Potato Fungicide Recipe
2 tablespoon baking soda 1/2 teaspoon oil or bleach free liquid soap 1 gallon water Mix all ingredients thoroughly. Use as you would a commercial potato fungicide.
