Whether you are caring for a lush vegetable garden or a flowerbed for pollinators, verticillium wilt is a threat. The best way to deal with this dreaded plant disease is avoiding it, but before you can protect your plants, you must first understand this deadly plant nemesis.

What Is Verticillium Wilt?

Verticillium wilt is fungal disease affecting over 350 host plants found throughout the world. It's caused by the soil-dwelling Verticillium dahliae and Verticillium. albo-atrum. This fungus grows into plant roots and stems, depriving plants of necessary nutrients for proper growth and clogging plants' water transport systems. It's is most active in cooler weather but may also affect plants in warmer weather due to previous damage.

Signs of Verticillium Wilt in Plants

Plants affected by this fungus show certain signs, including faded yellow or green leaves that wilt and die. The lower leaves show signs before upper plant leaves. Very young or non-woody plants may die quickly. However, signs of disease can differ by plant type. Here are some signs of verticillium wilt on commonly grown plants.

Common Susceptible Food Crops

Tomatoes and cucumbers are often staples in many home gardens, and unfortunately susceptible to verticillium fungi. Signs of disease for both plants includes wilting of older plant leaves and stunted growth. You may notice a brown v-shaped pattern on affected leaves as well. The only cure is to remove affected plants. You can help to prevent future infections with crop rotation, planting tomatoes in well-drained soil, and choosing resistant varieties.

Strawberries are a favorite summer fruit. They too are often victims of verticillium fungi living in your soil. Affected plants leaves have brown edges and veins, mainly lower plant leaves. These leaves often die. Plants also produce few new leaves. You'll need to dig out and destroy infected plants, and like tomatoes and cucumbers, choose disease-resistant varieties to ensure healthy growth.

Common Susceptible Flowers

Roses are very common ornamental plants, but also susceptible to this fungus. Sick plants develop drying canes, and new leaves are stunted and yellow. The plants may die if swift action isn't taken. Trim out infected canes at soon as signs develop. Once too many canes are affected and the plant is dying, the only solution is to uproot the plant.

Chrysanthemums are an excellent addition to a sustainable garden, but they too can be infected with verticillium fungi. The disease shows signs at the base of the plant first with leaves that turn yellow and die. The plant will also produce very few if any, blooms.

Dahlia blooms are always a great addition to your garden but can also be affected by verticillium fungi. The plant's lower leaves turn yellow, its blooms droop, and you may also notice dark brown areas on plant stems. In most cases, you'll need to remove sick plants and trim any decayed areas from stored tubers to prevent disease.

Avoiding Verticillium Wilt

There is no cure for this disease, so your best chance of a healthy garden is preventing the fungi from living in your soil. You can achieve this by utilizing good gardening practices.

Proper watering and fertilization is essential to growing healthy plants. Making sure soil has plenty of nitrogen and good drainage is a good start. Also avoid overwatering plants!

Rotation also helps. Rotate your susceptible plants using a four-year cycle.

Solarization is another possible solution. In sunny, warm areas you can cover your garden area with a tarp and allow the heat to build up and kill the fungi.

If you know your soil is contaminated, you can choose from a variety of plants that are naturally immune to this disease. Some examples include beans, asparagus, corn, lettuce, onions, peas, sweet potatoes, and carrots.

These quick tips can help you in growing healthy plants that are free of this dreaded fungus. If you do find yourself struggling with this disease, we've put together a comprehensive list of plants that are susceptible, immune, and resistant to Verticillium Wilt.