Verticillium wilt of viburnum is caused by a fungal infection that can lead to devastating damage to your home garden plant. Through careful care and planning, there are methods to avoid experiencing verticillium wilt, though its presence may be widespread in your landscape's soil. Become familiar with diagnosis as well as effective management to keep your home landscape full of healthy, vigorous viburnums.
Viburnum plants have a greater chance of resisting and fighting off fungal infections like verticillium wilt when kept vigorous as opposed to damaged, unhealthy plants. Grow viburnums in a landscape that offers full sun exposure, according to the Clemson University Extension. Viburnums will still grow in shaded conditions, but for healthy production of fruit, sun is necessary. Viburnums prefer moist, well-drained soil with a pH of 5.5. to 6.5.
Verticillium wilt fungal infections are caused by the fungi Verticillium albo-atrum and V. dahliae that attack a wide variety of woody plants including viburnums, according to the Ohio State University Extension. Other highly susceptible plants include ash, elm, magnolia and tuliptrees. The fungi inhabit soil for several years and invade through root systems, in addition to spreading from one plant to another.
Look for brown leaf edges, leaf wilt, stunted foliage, streaks of discoloration on cambium and the appearance of burned leaves as symptoms of a verticillium wilt infection. In extreme cases and particularly when left untreated, viburnums may experience branch dieback and can die in as little as two years, according to the Ohio State University Extension.
A solid prevention method is the planting of resistant plants instead of those that are highly susceptible. Especially if your tree dies, it is important during replanting to choose a species that will not fall ill to the fungal-borne pathogens. Plants resistant to verticillium wilt include, but are not limited to, crabapple, beech, dogwood, honeylocust, oak, sycamore and willow, according to the Ohio State University Extension.
Chemical control options like fungicides are ineffective in the treatment of verticillium wilt on viburnums. The best management method is the employment of consistent care and careful transplanting. Ensure plants are healthy before planting. Additionally, remove and destroy affected plant parts to prevent the insistence of the disease. Avoid drought conditions as well as waterlogged soil, both of which create an ideal environmental for fungal invasion, according to the Ohio State University Extension. Handle trees with care as wounds and even minor injuries provide a point of entrance for fungi. Always sanitize pruning tools between cuts and from one viburnum to the next to inhibit the chance of disease transfer.