Because verticillium wilt is not a curable disease, treatment revolves around giving the plant adequate water, light and nutrition to fight the disease. While killing verticillium wilt once it enters and infects a plant is not possible, preventing future infections by killing the fungus in the soil is possible.
A common yet ineffective treatment for verticillium wilt involves removing any leaves that exhibit discoloration or wilting from the plant. Not only is this method infeasible with large plants such as trees, it also does nothing to contain the pathogen's spread. Unfortunately, by the time a plant's leaves become wilted or discolored, the infection is already irreversible.
Most healthy plants can fight off a verticillium wilt infection with proper care. While giving a plant adequate fertilizer, water and sun does not guarantee survival, it gives the plant a better chance of fighting off the disease. However, some strains of verticillium wilt are particularly virulent, and even healthy plants cannot withstand these serious infections.
If a virulent strain of verticillium becomes established in your garden, prevent future infections by killing the fungus in the soil. Soil fumigants can kill most strains of verticillium in the soil. A non-chemical option is heating the soil to a high temperature. Cover the beds with thick plastic sheets, using rocks or stakes to keep the plastic in contact with the soil. Over the course of about a month, the sun heats the soil to temperatures higher than verticillium can tolerate, eventually killing the fungus.